In the magnetic field pattern around the solenoid, the field lines are denser near the poles, showing that the magnetic field is stronger at these regions outside the solenoid. The direction of the field is from the north pole to the south pole outside the solenoid. When the electric current in theRead more
In the magnetic field pattern around the solenoid, the field lines are denser near the poles, showing that the magnetic field is stronger at these regions outside the solenoid. The direction of the field is from the north pole to the south pole outside the solenoid. When the electric current in the circuit is reversed, the direction of the magnetic field also reverses, interchanging the north and south poles of the solenoid while maintaining the same magnetic field strength.
A wire of total resistance R is divided into three equal parts, so each part has resistance R/3. When these three equal parts are connected in parallel, the reciprocal of the equivalent resistance is the sum of their reciprocals. Hence, 1/R₁ = 3 × (1/(R/3)) = 9/R. Therefore, the equivalent resistancRead more
A wire of total resistance R is divided into three equal parts, so each part has resistance R/3. When these three equal parts are connected in parallel, the reciprocal of the equivalent resistance is the sum of their reciprocals. Hence,
1/R₁ = 3 × (1/(R/3)) = 9/R.
Therefore, the equivalent resistance R₁ = R/9. The ratio of the equivalent resistance to the original resistance is R₁ : R = 1 : 9, showing that resistance decreases nine times.
Excessive use of chemicals and pesticides in agriculture harms the environment because these substances contaminate soil, water, and air. They kill beneficial microorganisms and insects, reduce soil fertility, and enter the food chain, affecting animals and humans. Persistent chemicals accumulate inRead more
Excessive use of chemicals and pesticides in agriculture harms the environment because these substances contaminate soil, water, and air. They kill beneficial microorganisms and insects, reduce soil fertility, and enter the food chain, affecting animals and humans. Persistent chemicals accumulate in ecosystems, causing long-term damage. Overuse also leads to pesticide resistance in pests, forcing farmers to use stronger chemicals, further worsening environmental pollution and ecological imbalance.
The hind-brain of the human brain consists of the cerebellum, pons, and medulla oblongata. Among these, the medulla oblongata controls involuntary actions such as blood pressure, heart rate, salivation and breathing, ensuring vital bodily functions continue automatically without conscious effort. ItRead more
The hind-brain of the human brain consists of the cerebellum, pons, and medulla oblongata. Among these, the medulla oblongata controls involuntary actions such as blood pressure, heart rate, salivation and breathing, ensuring vital bodily functions continue automatically without conscious effort. It acts as a regulatory center for essential life processes, coordinating signals between the brain and spinal cord. The cerebellum mainly controls balance and coordination, while the pons assists in communication within the brain.
ANSWER: (a) All F₁ seeds are round and yellow. Genotype: RrYy. (b) Gametes from F₁: RY, Ry, rY, ry. F₂ phenotypes and ratio (from a 4×4 Punnett): Round, Yellow = 9/16 Round, Green = 3/16 Wrinkled, Yellow = 3/16 Wrinkled, Green = 1/16 (c) New trait combinations appear in F₂ because of independent assRead more
ANSWER: (a) All F₁ seeds are round and yellow. Genotype: RrYy.
(b) Gametes from F₁: RY, Ry, rY, ry.
F₂ phenotypes and ratio (from a 4×4 Punnett):
Round, Yellow = 9/16
Round, Green = 3/16
Wrinkled, Yellow = 3/16
Wrinkled, Green = 1/16
(c) New trait combinations appear in F₂ because of independent assortment of the two gene pairs during meiosis (alleles for seed shape and seed colour segregate into gametes independently), producing recombinant genotypes and the 9:3:3:1 phenotypic ratio.
Refer to the image below and state how the magnetic field pattern indicates regions where the magnetic field is stronger outside the magnet? What happens to the magnetic field when the current in the circuit is reversed?
In the magnetic field pattern around the solenoid, the field lines are denser near the poles, showing that the magnetic field is stronger at these regions outside the solenoid. The direction of the field is from the north pole to the south pole outside the solenoid. When the electric current in theRead more
In the magnetic field pattern around the solenoid, the field lines are denser near the poles, showing that the magnetic field is stronger at these regions outside the solenoid. The direction of the field is from the north pole to the south pole outside the solenoid. When the electric current in the circuit is reversed, the direction of the magnetic field also reverses, interchanging the north and south poles of the solenoid while maintaining the same magnetic field strength.
See lessA piece of wire of resistance R is cut into three equal parts. These parts are then connected in parallel. If the equivalent resistance of this parallel combination is R1, what is the value of the ratio R1 : R?
A wire of total resistance R is divided into three equal parts, so each part has resistance R/3. When these three equal parts are connected in parallel, the reciprocal of the equivalent resistance is the sum of their reciprocals. Hence, 1/R₁ = 3 × (1/(R/3)) = 9/R. Therefore, the equivalent resistancRead more
A wire of total resistance R is divided into three equal parts, so each part has resistance R/3. When these three equal parts are connected in parallel, the reciprocal of the equivalent resistance is the sum of their reciprocals. Hence,
See less1/R₁ = 3 × (1/(R/3)) = 9/R.
Therefore, the equivalent resistance R₁ = R/9. The ratio of the equivalent resistance to the original resistance is R₁ : R = 1 : 9, showing that resistance decreases nine times.
“Excessive use of chemicals and pesticides in agriculture adversely affect the environment.’’ Justify this statement.
Excessive use of chemicals and pesticides in agriculture harms the environment because these substances contaminate soil, water, and air. They kill beneficial microorganisms and insects, reduce soil fertility, and enter the food chain, affecting animals and humans. Persistent chemicals accumulate inRead more
Excessive use of chemicals and pesticides in agriculture harms the environment because these substances contaminate soil, water, and air. They kill beneficial microorganisms and insects, reduce soil fertility, and enter the food chain, affecting animals and humans. Persistent chemicals accumulate in ecosystems, causing long-term damage. Overuse also leads to pesticide resistance in pests, forcing farmers to use stronger chemicals, further worsening environmental pollution and ecological imbalance.
See lessName the parts of hind-brain of the human brain. Which part of the hind-brain controls involuntary actions such as blood pressure and salivation?
The hind-brain of the human brain consists of the cerebellum, pons, and medulla oblongata. Among these, the medulla oblongata controls involuntary actions such as blood pressure, heart rate, salivation and breathing, ensuring vital bodily functions continue automatically without conscious effort. ItRead more
The hind-brain of the human brain consists of the cerebellum, pons, and medulla oblongata. Among these, the medulla oblongata controls involuntary actions such as blood pressure, heart rate, salivation and breathing, ensuring vital bodily functions continue automatically without conscious effort. It acts as a regulatory center for essential life processes, coordinating signals between the brain and spinal cord. The cerebellum mainly controls balance and coordination, while the pons assists in communication within the brain.
See lessA pure pea plant having round (R), yellow (Y) seeds is crossed with another pure pea plant having wrinkled (r), green (y) seeds. Subsequently F1 progeny is self-pollinated to obtain F2 progeny. (a) What do the seeds of F1 generation look like? (b) Give the possible combinations of traits in seeds of F2 generation. Also give their ratio. (c) State the reason of obtaining seeds of new combination of traits in F2 generation.
ANSWER: (a) All F₁ seeds are round and yellow. Genotype: RrYy. (b) Gametes from F₁: RY, Ry, rY, ry. F₂ phenotypes and ratio (from a 4×4 Punnett): Round, Yellow = 9/16 Round, Green = 3/16 Wrinkled, Yellow = 3/16 Wrinkled, Green = 1/16 (c) New trait combinations appear in F₂ because of independent assRead more
ANSWER: (a) All F₁ seeds are round and yellow. Genotype: RrYy.
(b) Gametes from F₁: RY, Ry, rY, ry.
F₂ phenotypes and ratio (from a 4×4 Punnett):
(c) New trait combinations appear in F₂ because of independent assortment of the two gene pairs during meiosis (alleles for seed shape and seed colour segregate into gametes independently), producing recombinant genotypes and the 9:3:3:1 phenotypic ratio.
See less