Rao M. Shafqat wrote at 2011-05-23 21:20:34
10.the system will slow down because with the increase in the mass of the system.its moment of inertia will be increased and to conserve the angular momentum,the system have to rotate with less angular velocity.
Rudeema Chughtai. wrote at 2012-12-25 07:14:36
4-A car accelerates along a road due to force of friction between the road and the wheels of the car.The engine of the car tends the wheels to rotate and when they come in contact with the road,a frictional force is applied. Accordind to newton's 3 law of motion,every action has an equal but opposite reaction,so the wheels pushes the road backward and the road pushes the wheels in forward direction.As the wheels are attached to the car so the car moves in forward direction.
I hope this works.