(a) If the gravitational force between two objects is 1.3N, what will the gravitational force be if their separation becomes four times of its original values? (b) A Ferris wheel with a radius of 9 [11 makes one complete rotation every 10 seconds. D (i) Using the fact that the distance traveled by a rider in one rotation is 231', the circumference of the wheel, nd the speed with which the riders are moving. Take 1r = 3.14. (ii) What 1s the magnitude of their centripetal acceleration? (iii) What 1s the magnitude of the normal force exerted by the seat on a 48 kg rider at the top of the cycle? 1