Question

9a.(1 mork A planet has radius R. At a distance * above the surface of the planet the gravitational field strength is and the gravitational potential is V State what is meant by gravitational fSeld strength ob. 12 marks Show that V- -gtR+h) 9c. [2 marks) Draw a graph, on the sxes, to show the variation of the gravitational potential V of the planet with height h above the surface of the planet. A planet hss a radius of 3.1 10 m.At a point Pa distance 24 the gravitational field strength is 2.2 N kET appropriate unit for your answer 10 m above the surface of the planet .Calculate the gravitational poteestial at point P.include an I 9e. [3 marks The diagram shows the path of an asterold as it moves past the planet path of asterod poinm P planet lanet it had negligible speed Estimate the speed of the When the asteroid was far away from the p asterold at point P as defined in (b).

Answer 1

9a.Gravitational field strength means the force by which an body attract another body.

9b.
Gravitational field strength means the force by which an body attract another body 9b we know at any point g = G M/r^2 so at r = R + L g = G M/(R + L)^2 - (1) so V = + integral^(R + h)_- infinity G M/r^2 d r = -G M/(R + h) from (1) we get V = -g (R + h) \r\n 9d V = -g (R + h0 = -2.2 times (3.1 times 10^6 + 2.4 times 10^7) = -2.2 times 27.1 times 10^6 V = 59.62 times 10^6 J (g = Joule) \r\n if V_o is the velocity at P then at infinity kinetic energy and potential energy both are Zero so 1/2 m V_o^2 + V = 0 or 1/2 m V_o^2 = g (R + h) V_o = squareroot