9702/41/O/N/23: (a) (i) State what is indicated by the direction of the gravitational field line at a point in a gravitational field.
(ii) Explain, with reference to gravitational field lines, why the gravitational field near the surface of the Earth is approximately constant for small changes in height.
(b) A large isolated uniform sphere has mass M and radius R. Point P lies on a straight line passing through the centre of the sphere, at a variable displacement x from the centre, as shown in Fig. 1.1. Fig. 1.2 shows the variation with x of the gravitational field g at point P due to the sphere for
the values of x for which P is inside the sphere. The magnitude of the gravitational field at the surface of the sphere is Y.
(i) Determine an expression for Y in terms of M and R. Identify any other symbols that you use.
(ii) Explain why, at the surface of the sphere, g always has the opposite sign to x.
(iii) Complete Fig. 1.2 to show the variation of g with x for values of x, up to ±3R, for which point P is outside the sphere.
Instagram Pocket Guide ( / etphysics )
More Resources (9702-physics.blogspot.com/)
Support us! ( / etphysics )
Tuition/Tutoring inquiries:
Email: etphysics.office@gmail.com
Whatsapp: wa.me/60126679171 (Ms Lee)
linktr.ee/etphysics
#CambridgeALevelPhysics