## Laws of Motion

Chapter Revision Test

Q1:  A person jumps from the roof of a house with a box of weight W on his head. What will be the weight of the box as experienced by the person during jump? [1]

Q2: Which of the following is scalar quantity? Inertia, force and linear momentum. [1]

Q3: Action and reaction forces do not balance each other. Why? [1]

Q4: A bird is sitting on the floor of a wire cage and the cage is in the hand of a boy. The bird starts flying in the cage. Will the boy experience any change in the weight of the cage? [2]

Q5: Why does a cyclist lean to one side, while going along curve? In what direction does he lean? [2]

Q6: How does banking of roads reduce wear and tear of the tyres? [2]

Q7: A monkey of mass 40 kg climbs on a rope which can stand a maximum tension 600 N. In which of the following cases will the rope break? The monkey
(a) climbs up with an acceleration of 6m/s²
(b) climbs down with an acceleration of 4m/s²
(c) climbs up with a uniform seed of 5m/s
(d) falls down the rope freely under gravity.
Take g = 10m/s² and ignore the mass of the rope.

Q8: What is meant by coefficient of friction and angel of friction? Establish the relation between the two? [3]

OR
A block of mass 10kg is sliding on a surface inclined at a angle of 30° with the horizontal. Calculate the acceleration of the block. The coefficient of kinetic friction between the block and the surface is 0.5

Q9: State and prove the principle of law of conservation of linear momentum? [3]

Q10: A particle of mass 0.40 kg moving initially with constant speed of 10m/s to the north is subject to a constant force of 8.0 N directed towards south for 30s. Take at that instant, the force is applied to be t = 0, and the position of the particle at that time to be x = 0, predict its position at t = -5s, 25s, 30s? [3]