NTA Abhyas JEE Main2020PhysicsLaws of MotionPractice
The rear side of a truck is open and a box of mass 2 k g is placed on the truck 8 m away from the open end. The truck starts from rest with an acceleration of 2 m s - 2 on a straight road. The box will fall off the truck when it is at distance from the starting point equal to (in meter) (Given, μ = 0.1 and g = 10 m s - 2 ).
Correct answer
16
Step-by-step solution
Let a be the acceleration of truck, For block, m a - μ m g = m a 0 a 0 = a - μ g = 2 - 0.1 × 10 = 1 m / s 2 8 = 1 2 a 0 t 2 = 1 2 × 1 × t 2 ⇒ t = 4 s The block will fall off the truck after 4 s . For truck, Distance travelled by the truck in this time. s = 1 2 a t 2 = 1 2 × 2 × 4 2 = 16 m