Q1 The equation of motion for the freely dropped body under gravity is
- (a)`v^{2}` = 2ah
- (b) `v^{2}` = -2gh
- (c) `v^{2}` = -2ah
- (d) `v^{2}` = 2gh
- (d) v^{2} = 2gh
Q2 The stopping distance 'S' of a vehicle who is moving with initial velocity 'u'
- (a) S= `\frac{u^{2}}{2a}`
- (b) S= `\frac{a^{2}}{2u}`
- (c) S= `\frac{-u^{2}}{2a}`
- (d) None of these
- S= `\frac{-u^{2}}{2a}`
Q3 The ratio of the distance travel by a body falling freely from rest in first, second and third second of its fall is:-
- (a)2 : 3 : 5
- (b) 1 : 3 : 5
- (c) 5 : 3 :1
- (d) 3 : 5 : 1
- (b) 1 : 3 : 5 ( u=0, use formula `h_{nth}`= u+`\frac{g}{2}`(2n-1)
Q4 A balloon rising vertically up with a uniform velocity 15m/s releases a ball at a height of 100m. Calculate the time taken by the ball to hit the ground? g=10ms/2
- (a)7.5s
- (b) 5.7s
- (c) 6.2s
- (d) 6.9s
- (c) 6.2s
Q5 When a body falls freely under gravity, its velocity increases and g is positive.
- a) True
- b) False
- a) True
Q6 When a body thrown upward its velocity increases, g is negative.
- a) True
- b) False
- b) False
Q7 For a normal person, the reaction time is
- a) `\frac{1}{15}s`
- b) `\frac{1}{50}s`
- c) `\frac{1}{10}s`
- d) 0 s
- a) `\frac{1}{15}s`
Q8 The distance travelled by vehicle after it stops before the applied brakes is called stopping distance.
- a) True
- b) False
- b) False
Q9. The time interval between seeing a child and pressing the brake is known as
- a) Reaction time
- b) stopping time
- c) parallactic second
- d) None of these
- a) Reaction time
Q10 .......acceleration is called deceleration
- a) +ve acceleration
- b) -ve acceleration
- c) zero acceleratio
- d) All of above
- b) -ve acceleration