Sketch a graph on the axes provided below to show the relationship between the gravitational potential V with distance r above the surface of the planet.
As the asteroid enters the planet's atmosphere, it begins as a small point of light which grows much brighter and faster as it moves towards the surface of the planet.
(d)
Discuss these observations. Your answer should make reference to g as well as the effect of the planet's atmosphere.
A different pair of equally charged objects, C and D, are brought close together. Equipotential lines at –10 V, –6 V and –2 V around C and D are shown.
Hydrogen atoms in an ultraviolet (UV) lamp make transitions from the first excited state to the ground state. Photons are emitted and are incident on a metallic, photoelectric surface as shown.
The photoelectric surface is grounded, and the variable power supply is adjusted so that the electric potential of the collecting surface is 1.5 V.
(a)
Describe the properties of the electric field between the photoelectric surface and the collecting plate.
Electrons are released from the photoelectric surface and move toward the collecting plate.
(c)
Determine the work done by the electric field on the electrons as they arrive at the midpoint between the photoelectric surface and the collecting plate.
Describe the motion of the electrons between the photoelectric plate and the collector plate. Your answer should consider the field at the edges of the plates.
The diagram shows part of the surface of planet P. The gravitational potential at the surface of planet P is –6 V and the gravitational potential at point X is –2 V.
(b)
On the grid, sketch and label the equipotential surface corresponding to a gravitational potential of –4 V.
A meteorite, very far from planet P, begins to fall to the surface with a negligibly small initial speed. The mass of planet P is 3.0 × 1021 kg and its radius is 2.3 × 106 m.
(c)
Calculate the speed at which the meteorite will hit the surface, assuming planet P has no atmosphere.
