1.Describe how you would find the centre of gravity of a piece of cardboard of irregular shape.
2.The figure represents a tray held horizontally by a glass of water. The tary has a weight of 6N amd supports a drink of weight 3N.The waiter provides a force at P. The tray may pivot about T.(THE DRAWING IS ATTACHED)
(i)Use the information to find the force provided by the waiter at P and the upward force the hand exerts at T.
(ii)The drink is moved along the tray closer to the hand.Is the force needed to keep the tary horizontal now less, greater or the same? Explain your answer.
(iii)How much work is done by the waiter in lifting the tray and drink through a geight of 0.6m?
Moments=Force X Distance
Work Done=Force X Distance
The Attempt at a Solution
2(i) 40cm X 3N=5cm X PN
(ii)The force is not less (BUT I CAN'T EXPLAIN WHY)
(iii)Work Done=0.6 X 6N=3.6J