The term "power of accommodation" refers to the ability of the eye to adjust its focus to see objects at different distances clearly. This adjustment is achieved through changes in the shape of the eye's crystalline lens. The eye has the ability to focus on objects at varying distances by changing tRead more
The term “power of accommodation” refers to the ability of the eye to adjust its focus to see objects at different distances clearly. This adjustment is achieved through changes in the shape of the eye’s crystalline lens.
The eye has the ability to focus on objects at varying distances by changing the curvature of the lens. When viewing objects up close, the ciliary muscles surrounding the lens contract, causing the lens to become thicker and more convex. This increased curvature allows the eye to focus on nearby objects.
Conversely, when looking at objects in the distance, the ciliary muscles relax, and the lens becomes flatter. This reduction in curvature enables the eye to focus on distant objects.
The power of accommodation is measured in diopters (D), and it represents the ability of the eye to adjust its focus from infinity to a certain distance. The unit of diopter is the reciprocal of the focal length measured in meters.
The power of accommodation tends to decrease with age, a condition known as presbyopia. Presbyopia is a natural aging process that makes it more difficult for the eyes to focus on close objects. This is one of the reasons why many people need reading glasses as they get older.
A person with myopia, also known as nearsightedness, can see objects up close clearly but has difficulty seeing distant objects. Myopia occurs when the eyeball is too long or the cornea has too much curvature, causing light entering the eye to focus in front of the retina instead of directly on it.Read more
A person with myopia, also known as nearsightedness, can see objects up close clearly but has difficulty seeing distant objects. Myopia occurs when the eyeball is too long or the cornea has too much curvature, causing light entering the eye to focus in front of the retina instead of directly on it.
To correct myopia and restore proper vision for distance viewing, a diverging or concave lens is used. A concave lens is thinner at the center and thicker at the edges. This type of lens helps to spread out the incoming light rays before they enter the eye, allowing them to converge properly on the retina. The use of a concave lens compensates for the excessive focusing power of the myopic eye.
In summary, for a person with myopia (nearsightedness) who cannot see objects beyond 1.2 meters distinctly, a concave or diverging lens should be prescribed to correct their vision for distant objects. The power of the concave lens would be determined by an eye examination, and it would be measured in diopters (D).
The total resistance of resistors or coils in series is the sum of their individual resistances, and for resistors or coils in parallel, the reciprocal of the total resistance is the sum of the reciprocals of their individual resistances. (a) Highest Total Resistance: For the highest total resistancRead more
The total resistance of resistors or coils in series is the sum of their individual resistances, and for resistors or coils in parallel, the reciprocal of the total resistance is the sum of the reciprocals of their individual resistances.
(a) Highest Total Resistance:
For the highest total resistance, you would connect the resistors in series because the total resistance in a series connection is the sum of the individual resistances.
R_total, series = R₁ + R₂ + R₃ + R₄
R_total, series = 4 + 8 + 12 + 24 = 48Ω
So, the highest total resistance is 48Ω when the resistors are connected in series.
(b) Lowest Total Resistance:
For the lowest total resistance, you would connect the resistors in parallel because the total resistance in a parallel connection is given by the reciprocal of the sum of the reciprocals of the individual resistances.
The cord of an electric heater does not glow while the heating element does because the cord and the heating element are typically made of different materials with different electrical and thermal properties. Material Selection: » The heating element of an electric heater is intentionally designed tRead more
The cord of an electric heater does not glow while the heating element does because the cord and the heating element are typically made of different materials with different electrical and thermal properties.
Material Selection:
» The heating element of an electric heater is intentionally designed to have a high electrical resistance and to generate heat when an electric current passes through it. This is achieved by using materials with high resistivity, such as certain alloys like nichrome.
» The cord, on the other hand, is usually made of materials with lower resistivity and is designed to conduct electricity with minimal loss. The primary function of the cord is to carry the electric current from the power source to the heating element.
2. Heat Generation:
» The heating element is specifically designed to convert electrical energy into heat. As a result, it heats up significantly when an electric current flows through it, and this heating causes it to glow.
» The cord, being designed for electrical conductivity rather than heat generation, is chosen for its ability to transmit electrical power efficiently without substantial heating.
3. Temperature Tolerance:
» The heating element is designed to withstand and operate at high temperatures. The material properties of the heating element allow it to reach the necessary temperatures for efficient heat generation without melting or deteriorating.
» The cord, however, is not designed to handle the high temperatures associated with heat generation. Using a cord material that could withstand the high temperatures of the heating element might not be practical or cost-effective.
In summary, the heating element and the cord are designed for different purposes and, therefore, have different material compositions and properties. The heating element is designed to glow and produce heat, while the cord is designed to conduct electricity efficiently without significant heat generation.
The heat (Q) generated when a charge (Q) moves through a potential difference (V) can be calculated using the formula: Q = V. I. t where: » Q is the heat generated, » V is the potential difference, » I is the current, and » t is the time. The current (I) can be calculated using Ohm's Law: I = V/R whRead more
The heat (Q) generated when a charge (Q) moves through a potential difference (V) can be calculated using the formula:
Q = V. I. t
where:
» Q is the heat generated,
» V is the potential difference,
» I is the current, and
» t is the time.
The current (I) can be calculated using Ohm’s Law:
I = V/R
where:
» R is the resistance.
If we rearrange the formula for current and substitute it into the formula for heat, we get:
Q = V . v/R . t
Now, we need to know the resistance (R) to calculate the current. If the resistance is not provided, we cannot determine the exact amount of heat generated. However, if we assume that the circuit is purely resistive, we can use Ohm’s Law to find R as R = V/I.
Let’s proceed with this assumption:
R = V/I = V/V/R = R
So, in the case of a purely resistive circuit, R remains constant.
Now, substitute the values into the formula for heat:
Q = V . V/R . t
Q = V^2 t/R
Given:
V = 50 V
t = 1 hour = 3600 seconds
Assuming R is constant, we can calculate the heat generated using the provided potential difference and time:
Q = (50V)² 3600s/R
Please note that without information about the resistance (R), we cannot determine the actual heat generated. If you have the resistance value, you can substitute it into the formula to get the precise result.
The heat (Q) developed in an electric circuit can be calculated using the formula: Q = I² . R . t where: » Q is the heat developed, » I is the cerrent, » R is the resistance, and » t is the time. Given: I = 5A(current) R = 20Ω (resistance) t = 30s (time) Substitude these values into the formula; Q =Read more
The heat (Q) developed in an electric circuit can be calculated using the formula:
Q = I² . R . t
where:
» Q is the heat developed,
» I is the cerrent,
» R is the resistance, and
» t is the time.
Given:
I = 5A(current)
R = 20Ω (resistance)
t = 30s (time)
The resistance of a conductor depends on several factors, and it can be determined using Ohm's Law, which states that: R = V/I where: » R is the resistance, » V is the voltage across the conductor, and » I is the current flowing through the conductor. The factors influencing the resistance of a coRead more
The resistance of a conductor depends on several factors, and it can be determined using Ohm’s Law, which states that:
R = V/I
where:
» R is the resistance,
» V is the voltage across the conductor, and
» I is the current flowing through the conductor.
The factors influencing the resistance of a conductor include:
1. Material: Different materials have different resistivities. Resistivity is an inherent property of a material that determines how strongly it resists the flow of electric current.
2. Length: The resistance is directly proportional to the length of the conductor. As the length increases, the resistance also increases.
3. Cross-sectional Area: The resistance is inversely proportional to the cross-sectional area of the conductor. A larger cross-sectional area allows for more current flow and reduces resistance.
4. Temperature: The temperature of the conductor can affect its resistance. In general, as the temperature increases, the resistance also increases. This effect is more pronounced in some materials than others.
The relationship between these factors is given by the formula:
R = ρ L/A
where:
» R is the resistance,
» ρ is the resistivity of the material,
» L is the length of the conductor, and
» A is the cross-sectional area of the conductor.
In summary, the resistance of a conductor depends on its material, length, cross-sectional area, and temperature.
Current will flow more easily through a thick wire compared to a thin wire of the same material when connected to the same source. This is due to the relationship between resistance, current, and the dimensions of the conductor. According to Ohm's Law ( R = V/I ), the resistance (R) of a conductor iRead more
Current will flow more easily through a thick wire compared to a thin wire of the same material when connected to the same source. This is due to the relationship between resistance, current, and the dimensions of the conductor.
According to Ohm’s Law ( R = V/I ), the resistance (R) of a conductor is inversely proportional to its cross-sectional area (A), given a constant resistivity (ρ) and length (L). The formula for resistance is:
R =ρ L/A
Here:
» R is resistance,
» ρ is the resistivity of the material,
» L is the length of the conductor, and
» A is the cross-sectional area.
Since resistance is inversely proportional to the cross-sectional area (A), a thicker wire with a larger cross-sectional area will have lower resistance compared to a thinner wire of the same material and length.
Lower resistance means that the wire offers less opposition to the flow of electric current. Therefore, current will flow more easily through the thicker wire, and it will experience less voltage drop along its length. This is why thicker wires are often used for applications where low resistance and efficient current flow are important, such as in power transmission lines.
Coils of electric toasters and electric irons are often made of an alloy rather than a pure metal for several reasons: 1. Resistance and Heating Properties: Alloys can be designed to have specific electrical resistance and heating properties. The resistance of a material is a crucial factor in the oRead more
Coils of electric toasters and electric irons are often made of an alloy rather than a pure metal for several reasons:
1. Resistance and Heating Properties: Alloys can be designed to have specific electrical resistance and heating properties. The resistance of a material is a crucial factor in the operation of heating elements. Alloys can be engineered to provide the desired resistance, allowing the toaster or iron to generate the appropriate amount of heat for its intended purpose.
2. High Melting Point: Heating elements in toasters and irons can reach high temperatures during operation. Alloys are often chosen because they can have higher melting points than pure metals, ensuring that the heating element remains stable and doesn’t melt or deform under the high temperatures.
3. Durability and Mechanical Strength: Alloys are often more durable and mechanically robust than pure metals. The mechanical strength of the heating element is important to withstand repeated heating and cooling cycles and mechanical stresses.
4. Corrosion Resistance: Alloys can be formulated to be more resistant to corrosion than pure metals. This is important in appliances like toasters and irons that may be exposed to moisture or humidity during use.
5. Cost-effectiveness: Alloys can be designed to provide the necessary properties at a lower cost than using a pure metal with similar characteristics. This consideration is often important in the manufacturing of appliances where cost efficiency is a significant factor.
One common alloy used for heating elements in appliances is nichrome, which is a nickel-chromium alloy. Nichrome has a high melting point, good electrical resistance, and is corrosion-resistant, making it well-suited for heating applications in electric toasters, irons, and other similar devices.
When resistors are connected in parallel, the reciprocal of the equivalent resistance (Req) is equal to the sum of the reciprocals of the individual resistances. The formula for resistances in parallel is given by: 1/Req = 1/R₁ + 1/R₂ + 1/R₃ + . . . For the given situation: 1/Req = 1/100 + 1/50 + 1/Read more
When resistors are connected in parallel, the reciprocal of the equivalent resistance (Req) is equal to the sum of the reciprocals of the individual resistances. The formula for resistances in parallel is given by:
1/Req = 1/R₁ + 1/R₂ + 1/R₃ + . . .
For the given situation:
1/Req = 1/100 + 1/50 + 1/500
Now, let’s calculate Req:
1/Req = 1/100 + 2/100 + 1/500
1/Req = 3/100 + 1/500
1/Req = 15/500 + 1/500
1/Req = 16/500
Req = 500/16
Req = 31.25Ω
So, the equivalent resistance of the electric lamp, toaster, and water filter connected in parallel is 31.25Ω.
Now, if the electric iron is to draw the same current as all three appliances combined, we can use Ohm’s Law ( V= I ⋅R) to find the current (I) through the equivalent resistance:
I = V /Req
I = 220/31.25
I ≈7.04A
Therefore, the resistance of the electric iron connected to the same source is 31.25Ω, and the current through it is approximately 7.04A.
What is meant by power of accommodation of the eye?
The term "power of accommodation" refers to the ability of the eye to adjust its focus to see objects at different distances clearly. This adjustment is achieved through changes in the shape of the eye's crystalline lens. The eye has the ability to focus on objects at varying distances by changing tRead more
The term “power of accommodation” refers to the ability of the eye to adjust its focus to see objects at different distances clearly. This adjustment is achieved through changes in the shape of the eye’s crystalline lens.
The eye has the ability to focus on objects at varying distances by changing the curvature of the lens. When viewing objects up close, the ciliary muscles surrounding the lens contract, causing the lens to become thicker and more convex. This increased curvature allows the eye to focus on nearby objects.
Conversely, when looking at objects in the distance, the ciliary muscles relax, and the lens becomes flatter. This reduction in curvature enables the eye to focus on distant objects.
The power of accommodation is measured in diopters (D), and it represents the ability of the eye to adjust its focus from infinity to a certain distance. The unit of diopter is the reciprocal of the focal length measured in meters.
The power of accommodation tends to decrease with age, a condition known as presbyopia. Presbyopia is a natural aging process that makes it more difficult for the eyes to focus on close objects. This is one of the reasons why many people need reading glasses as they get older.
See lessA person with a myopic eye cannot see objects beyond 1.2 m distinctly. What should be the type of the corrective lens used to restore proper vision?
A person with myopia, also known as nearsightedness, can see objects up close clearly but has difficulty seeing distant objects. Myopia occurs when the eyeball is too long or the cornea has too much curvature, causing light entering the eye to focus in front of the retina instead of directly on it.Read more
A person with myopia, also known as nearsightedness, can see objects up close clearly but has difficulty seeing distant objects. Myopia occurs when the eyeball is too long or the cornea has too much curvature, causing light entering the eye to focus in front of the retina instead of directly on it.
To correct myopia and restore proper vision for distance viewing, a diverging or concave lens is used. A concave lens is thinner at the center and thicker at the edges. This type of lens helps to spread out the incoming light rays before they enter the eye, allowing them to converge properly on the retina. The use of a concave lens compensates for the excessive focusing power of the myopic eye.
In summary, for a person with myopia (nearsightedness) who cannot see objects beyond 1.2 meters distinctly, a concave or diverging lens should be prescribed to correct their vision for distant objects. The power of the concave lens would be determined by an eye examination, and it would be measured in diopters (D).
See lessWhat is (a) the highest, (b) the lowest total resistance that can be secured by combinations of four coils of resistance 4 ohm, 8 ohm, 12 ohm, 24 ohm?
The total resistance of resistors or coils in series is the sum of their individual resistances, and for resistors or coils in parallel, the reciprocal of the total resistance is the sum of the reciprocals of their individual resistances. (a) Highest Total Resistance: For the highest total resistancRead more
The total resistance of resistors or coils in series is the sum of their individual resistances, and for resistors or coils in parallel, the reciprocal of the total resistance is the sum of the reciprocals of their individual resistances.
(a) Highest Total Resistance:
For the highest total resistance, you would connect the resistors in series because the total resistance in a series connection is the sum of the individual resistances.
R_total, series = R₁ + R₂ + R₃ + R₄
R_total, series = 4 + 8 + 12 + 24 = 48Ω
So, the highest total resistance is 48Ω when the resistors are connected in series.
(b) Lowest Total Resistance:
For the lowest total resistance, you would connect the resistors in parallel because the total resistance in a parallel connection is given by the reciprocal of the sum of the reciprocals of the individual resistances.
1/R_total, paraller = 1/R₁ + 1/R₂ + 1/R₃ + 1/R₄
1/R_total, paraller = 6/24 + 3/24 + 2/24 + 1/24
1/R_total, parallel = 12/24
See less
total, parallel = 2Ω
Rtotal, parallel = 2Ω
Why does the cord of an electric heater not glow while the heating element does?
The cord of an electric heater does not glow while the heating element does because the cord and the heating element are typically made of different materials with different electrical and thermal properties. Material Selection: » The heating element of an electric heater is intentionally designed tRead more
The cord of an electric heater does not glow while the heating element does because the cord and the heating element are typically made of different materials with different electrical and thermal properties.
Material Selection:
» The heating element of an electric heater is intentionally designed to have a high electrical resistance and to generate heat when an electric current passes through it. This is achieved by using materials with high resistivity, such as certain alloys like nichrome.
» The cord, on the other hand, is usually made of materials with lower resistivity and is designed to conduct electricity with minimal loss. The primary function of the cord is to carry the electric current from the power source to the heating element.
2. Heat Generation:
» The heating element is specifically designed to convert electrical energy into heat. As a result, it heats up significantly when an electric current flows through it, and this heating causes it to glow.
» The cord, being designed for electrical conductivity rather than heat generation, is chosen for its ability to transmit electrical power efficiently without substantial heating.
3. Temperature Tolerance:
» The heating element is designed to withstand and operate at high temperatures. The material properties of the heating element allow it to reach the necessary temperatures for efficient heat generation without melting or deteriorating.
» The cord, however, is not designed to handle the high temperatures associated with heat generation. Using a cord material that could withstand the high temperatures of the heating element might not be practical or cost-effective.
See lessIn summary, the heating element and the cord are designed for different purposes and, therefore, have different material compositions and properties. The heating element is designed to glow and produce heat, while the cord is designed to conduct electricity efficiently without significant heat generation.
Compute the heat generated while transferring 96000 coulomb of charge in one hour through a potential difference of 50 V.
The heat (Q) generated when a charge (Q) moves through a potential difference (V) can be calculated using the formula: Q = V. I. t where: » Q is the heat generated, » V is the potential difference, » I is the current, and » t is the time. The current (I) can be calculated using Ohm's Law: I = V/R whRead more
The heat (Q) generated when a charge (Q) moves through a potential difference (V) can be calculated using the formula:
Q = V. I. t
where:
» Q is the heat generated,
» V is the potential difference,
» I is the current, and
» t is the time.
The current (I) can be calculated using Ohm’s Law:
I = V/R
where:
» R is the resistance.
If we rearrange the formula for current and substitute it into the formula for heat, we get:
Q = V . v/R . t
Now, we need to know the resistance (R) to calculate the current. If the resistance is not provided, we cannot determine the exact amount of heat generated. However, if we assume that the circuit is purely resistive, we can use Ohm’s Law to find R as R = V/I.
Let’s proceed with this assumption:
R = V/I = V/V/R = R
So, in the case of a purely resistive circuit, R remains constant.
Now, substitute the values into the formula for heat:
Q = V . V/R . t
Q = V^2 t/R
Given:
V = 50 V
t = 1 hour = 3600 seconds
Assuming R is constant, we can calculate the heat generated using the provided potential difference and time:
Q = (50V)² 3600s/R
Please note that without information about the resistance (R), we cannot determine the actual heat generated. If you have the resistance value, you can substitute it into the formula to get the precise result.
See lessAn electric iron of resistance 20 ohm takes a current of 5 A. Calculate the heat developed in 30 s.
The heat (Q) developed in an electric circuit can be calculated using the formula: Q = I² . R . t where: » Q is the heat developed, » I is the cerrent, » R is the resistance, and » t is the time. Given: I = 5A(current) R = 20Ω (resistance) t = 30s (time) Substitude these values into the formula; Q =Read more
The heat (Q) developed in an electric circuit can be calculated using the formula:
Q = I² . R . t
where:
» Q is the heat developed,
» I is the cerrent,
» R is the resistance, and
» t is the time.
Given:
I = 5A(current)
R = 20Ω (resistance)
t = 30s (time)
Substitude these values into the formula;
Q = (5A)² . (20 Ω) . (30s)
Q = 25 A² . 20Ω . 30s
Q = 25 . 20 . 30 J
Q = 15,000 J
Therefore, the heat developed in the electric iron in 30 seconds is 15,000 joules.
See lessOn what factors does the resistance of a conductor depend?
The resistance of a conductor depends on several factors, and it can be determined using Ohm's Law, which states that: R = V/I where: » R is the resistance, » V is the voltage across the conductor, and » I is the current flowing through the conductor. The factors influencing the resistance of a coRead more
The resistance of a conductor depends on several factors, and it can be determined using Ohm’s Law, which states that:
R = V/I
where:
» R is the resistance,
» V is the voltage across the conductor, and
» I is the current flowing through the conductor.
The factors influencing the resistance of a conductor include:
1. Material: Different materials have different resistivities. Resistivity is an inherent property of a material that determines how strongly it resists the flow of electric current.
2. Length: The resistance is directly proportional to the length of the conductor. As the length increases, the resistance also increases.
3. Cross-sectional Area: The resistance is inversely proportional to the cross-sectional area of the conductor. A larger cross-sectional area allows for more current flow and reduces resistance.
4. Temperature: The temperature of the conductor can affect its resistance. In general, as the temperature increases, the resistance also increases. This effect is more pronounced in some materials than others.
The relationship between these factors is given by the formula:
R = ρ L/A
where:
» R is the resistance,
» ρ is the resistivity of the material,
» L is the length of the conductor, and
» A is the cross-sectional area of the conductor.
In summary, the resistance of a conductor depends on its material, length, cross-sectional area, and temperature.
See lessWill current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?
Current will flow more easily through a thick wire compared to a thin wire of the same material when connected to the same source. This is due to the relationship between resistance, current, and the dimensions of the conductor. According to Ohm's Law ( R = V/I ), the resistance (R) of a conductor iRead more
Current will flow more easily through a thick wire compared to a thin wire of the same material when connected to the same source. This is due to the relationship between resistance, current, and the dimensions of the conductor.
According to Ohm’s Law ( R = V/I ), the resistance (R) of a conductor is inversely proportional to its cross-sectional area (A), given a constant resistivity (ρ) and length (L). The formula for resistance is:
R =ρ L/A
Here:
» R is resistance,
» ρ is the resistivity of the material,
» L is the length of the conductor, and
» A is the cross-sectional area.
Since resistance is inversely proportional to the cross-sectional area (A), a thicker wire with a larger cross-sectional area will have lower resistance compared to a thinner wire of the same material and length.
Lower resistance means that the wire offers less opposition to the flow of electric current. Therefore, current will flow more easily through the thicker wire, and it will experience less voltage drop along its length. This is why thicker wires are often used for applications where low resistance and efficient current flow are important, such as in power transmission lines.
See lessWhy are coils of electric toasters and electric irons made of an alloy rather than a pure metal?
Coils of electric toasters and electric irons are often made of an alloy rather than a pure metal for several reasons: 1. Resistance and Heating Properties: Alloys can be designed to have specific electrical resistance and heating properties. The resistance of a material is a crucial factor in the oRead more
Coils of electric toasters and electric irons are often made of an alloy rather than a pure metal for several reasons:
1. Resistance and Heating Properties: Alloys can be designed to have specific electrical resistance and heating properties. The resistance of a material is a crucial factor in the operation of heating elements. Alloys can be engineered to provide the desired resistance, allowing the toaster or iron to generate the appropriate amount of heat for its intended purpose.
2. High Melting Point: Heating elements in toasters and irons can reach high temperatures during operation. Alloys are often chosen because they can have higher melting points than pure metals, ensuring that the heating element remains stable and doesn’t melt or deform under the high temperatures.
3. Durability and Mechanical Strength: Alloys are often more durable and mechanically robust than pure metals. The mechanical strength of the heating element is important to withstand repeated heating and cooling cycles and mechanical stresses.
4. Corrosion Resistance: Alloys can be formulated to be more resistant to corrosion than pure metals. This is important in appliances like toasters and irons that may be exposed to moisture or humidity during use.
5. Cost-effectiveness: Alloys can be designed to provide the necessary properties at a lower cost than using a pure metal with similar characteristics. This consideration is often important in the manufacturing of appliances where cost efficiency is a significant factor.
One common alloy used for heating elements in appliances is nichrome, which is a nickel-chromium alloy. Nichrome has a high melting point, good electrical resistance, and is corrosion-resistant, making it well-suited for heating applications in electric toasters, irons, and other similar devices.
See lessAn electric lamp of 100 ohm, a toaster of resistance 50 ohm, and a water filter of resistance 500 ohm are connected in parallel to a 220 V source. What is the resistance of an electric iron connected to the same source that takes as much current as all three appliances, and what is the current through it?
When resistors are connected in parallel, the reciprocal of the equivalent resistance (Req) is equal to the sum of the reciprocals of the individual resistances. The formula for resistances in parallel is given by: 1/Req = 1/R₁ + 1/R₂ + 1/R₃ + . . . For the given situation: 1/Req = 1/100 + 1/50 + 1/Read more
When resistors are connected in parallel, the reciprocal of the equivalent resistance (Req) is equal to the sum of the reciprocals of the individual resistances. The formula for resistances in parallel is given by:
1/Req = 1/R₁ + 1/R₂ + 1/R₃ + . . .
For the given situation:
1/Req = 1/100 + 1/50 + 1/500
Now, let’s calculate Req:
1/Req = 1/100 + 2/100 + 1/500
1/Req = 3/100 + 1/500
1/Req = 15/500 + 1/500
1/Req = 16/500
Req = 500/16
Req = 31.25Ω
So, the equivalent resistance of the electric lamp, toaster, and water filter connected in parallel is 31.25Ω.
Now, if the electric iron is to draw the same current as all three appliances combined, we can use Ohm’s Law ( V= I ⋅R) to find the current (I) through the equivalent resistance:
I = V /Req
I = 220/31.25
I ≈7.04A
Therefore, the resistance of the electric iron connected to the same source is 31.25Ω, and the current through it is approximately 7.04A.
See less