Question

(C) Solve the given numerical problems.
1. A man is running on the straight road with the uniform velocity of
3 m/s. Calculate acceleration produced by him. [Ans: 0 m/s2
]
2. A motorcycle starting from rest covers 200 metre distance in
6 second. Calculate final velocity and acceleration of the motorcycle.
[Ans: a = 11.1 m/s2 , v = 66.6 m/s]
3. A bus is moving with the velocity of 36 km/hr. After seeing a boy
at 20 m ahead on the road, the driver applies the brake and the bus
gets stopped at 10 m distance. Now, calculate retardation as well as
time taken by this bus to stop. [Ans: a = -10 m/s2 , t = 1s]
4. A train is moving with the velocity of 45 km/hr. The driver applies
brake and the train gets stopped in 6 second. Now, calculate
retardation as well as distance covered by the train before coming
to the rest]. [Ans: a = 2.08 m/s2 , s = 112.44 m]
5. A car starting from rest attains a velocity of 90 km/hr in 10 second.
Now, calculate acceleration as well as distance covered by the car.
[Ans: a = 2.5 m/s2 , s = 125 m]
6. A car of 900 kg mass is moving at the velocity of 60 km/hr. It is
brought into rest at 50 metre distance by applying brake. Now,
calculate the force required to stop the car. [Ans: 2500 N]

Answer 1

Answer:

1. As acceleration=change in velocity /time taken and change in velocity of man is zero because he in uniform velocity so acc. is zero