- Messages
- 129
- Reaction score
- 306
- Points
- 73
8: The velocity is constant for the first part and the second part but both are different. So acceleration is not constant. Also, there is no evidence that speed is zero at the start so B is wrong. Its not a straight line so distance is not proportional. Speed changes so D.
10: At X, sand is stationary and truck is moving so when they stick together the speed decreases.
At Y, sand also leaves with some speed and as the total mass remains same, the speed will not change.
23: Elastic potential or strain energy is calculated by area under force-extension graph. This is greatest in B.
I don't understand what happens at Y in question 10. The total mass of what remains the same? The sand falls away, so the total mass should be less.