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The earth is assumed to be a sphere of radius R. A platform is arranged at a height R from the surface of the earth. The escape velocity of a body from this platform is fv, where v is its escape velocity from the surface of the earth. The value of f is
The escape velocity is defined as the minimum speed by which a body has to move away from the influence of a planet's gravitational pull without further propulsion. For Earth, it would depend on how far a distance one moves away from the center of the Earth. The escape velocity is proportional to thRead more
The escape velocity is defined as the minimum speed by which a body has to move away from the influence of a planet’s gravitational pull without further propulsion. For Earth, it would depend on how far a distance one moves away from the center of the Earth. The escape velocity is proportional to the square root of the reciprocal of the radius R of the Earth at the surface.
Now consider a platform located at a height equal to the radius of the Earth (R) above its surface. This makes the total distance from the Earth’s center to the platform (2R). Since escape velocity decreases with an increase in distance from the planet’s center, the escape velocity from this platform is less than that from the Earth’s surface.
This, knowing that escape velocity varies in inverse proportion to the distance from the center’s square root, makes escape velocity at a distance of 2R a fraction of the surface escape velocity. The factor f linking between the two velocities can then be calculated as follows, 1/√2 . Therefore, if the escape velocity from earth’s surface is some quantity ‘a’, then from this ‘platform’ it becomes an amount ‘a divided by f’.
This shows that gravity depends on distance, indicating that the escape velocity at altitude varies.
See lessIdentify the part of the electromagnetic spectrum which is produces by bombarding a metal target by high speed electrons.
X-rays are produced by bombarding a metal target with high-speed electrons. They belong to the electromagnetic spectrum with frequencies ranging from 30 PHz to 30 EHz and are used in medical imaging and material analysis. For more visit here: https://www.tiwariacademy.com/ncert-solutions/class-12/phRead more
X-rays are produced by bombarding a metal target with high-speed electrons. They belong to the electromagnetic spectrum with frequencies ranging from 30 PHz to 30 EHz and are used in medical imaging and material analysis.
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See lesshttps://www.tiwariacademy.com/ncert-solutions/class-12/physics/chapter-8/
For a satellite velocity from earth is 11.2 km/s. If a body is to be launched at an angle of 60ᵒ with the vertical, then escape velocity will be
While ejecting a body from the Earth, escape velocity becomes very crucial to overcome gravitational force so that it becomes free from the planet's influence. The conventional value of escape velocity from Earth's surface is about 11.2 km/s. But if the launch angle is considered to be 60 degrees wiRead more
While ejecting a body from the Earth, escape velocity becomes very crucial to overcome gravitational force so that it becomes free from the planet’s influence. The conventional value of escape velocity from Earth’s surface is about 11.2 km/s. But if the launch angle is considered to be 60 degrees with the vertical, then the whole speed needed for escape becomes a different story.
The required launch velocity, at an angle, would be the summation of the components of velocity. The vertical component needs to equal the escape velocity so that the body can rise infinitely against the gravity of Earth. Now, for an angle of 60 degrees, we find that in relation between the required launch velocity and the escape velocity, it shows that the necessary velocity for escape is increasing.
Specifically, when launched at an angle of 60 degrees, the total velocity needed becomes approximately 11√3 km/s. This is because the vertical component of the launch velocity has to compensate for the angle at which the body is launched. Consequently, a launch speed of 11√3 km/s guarantees that the vertical component will match the required escape velocity of 11.2 km/s and the body will break free from Earth’s gravitational influence. This is how launch angle affects the dynamics of reaching escape velocity.
See lessName the part of electromagnetic spectrum which is suitable for (i) radar systems used in aircraft navigation. (ii) treatment of cancer tumours.
(i) Microwaves are suitable for radar systems used in aircraft navigation, with frequencies ranging from 1 GHz to 300 GHz. (ii) Gamma rays are used for treating cancer tumors, with frequencies above 30 EHz. For more visit here: https://www.tiwariacademy.com/ncert-solutions/class-12/physics/chapter-8Read more
(i) Microwaves are suitable for radar systems used in aircraft navigation, with frequencies ranging from 1 GHz to 300 GHz.
(ii) Gamma rays are used for treating cancer tumors, with frequencies above 30 EHz.
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See lesshttps://www.tiwariacademy.com/ncert-solutions/class-12/physics/chapter-8/
The escape velocity from earth is 11.2 km/s. If a body is to be projected in a direction making an angle 45° to the vertical, then the escape velocity is
Escape velocity is defined as the minimum speed for an object to break away from the gravitational pull of a celestial body, say Earth. For Earth, this escape velocity is around 11.2 km/s. If a body is projected vertically upwards, reaching this speed enables it to overcome gravitational attractionRead more
Escape velocity is defined as the minimum speed for an object to break away from the gravitational pull of a celestial body, say Earth. For Earth, this escape velocity is around 11.2 km/s. If a body is projected vertically upwards, reaching this speed enables it to overcome gravitational attraction without needing any further propulsion.
In the case of launching at an angle, the scenario is different. If the projection is made at an angle of 45 degrees with respect to the vertical, then the launch velocity would need to be adjusted so that the vertical component was equal to the escape velocity at the given point. With the Earth’s gravity present, this would ensure indefinite ascent of the body projected. For an angle of 45 degrees, a relation between the total velocity at launch and the escape velocity is critical.
More precisely, the launching speed required now becomes 11.2√2 km/s when launched at this angle of projection. The adjustment in this case will take into account both the need to maintain enough momentum upwards and the angle of projection. By attaining this higher speed, it ensures that the vertical component of the velocity is high enough to escape Earth’s gravitational pull. This shows how the launching angles impact significantly on the dynamics involved in achieving escape velocity.
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