A particle moves according to the equation x = t2 + 3t + 4. The average velocity in the first 5 s is
The resistive force suffered by a motor boat is αV2 where V is instantaneous velocity. The engine was shut down when the velocity of the boat was V0. Find the average velocity at any time t.
A body throws a ball to his friend 20 m away. The ball reaches to the friend in 4s. The friend then throws the ball back to boy and it reaches the boy in 5s. assume the ball travels with constant velocity during any throw.
A stone is dropped from a certain road. He takes 5 steps forward and 3 steps backward and so on. Each step is 1 m long and takes 1s. There is a pit on the road 11 m away from the starting point. The drunkard will fall into the pit after
A body sliding on a smooth inclined plane requires 5 s to reach the bottom, starting from rest at the top. How much time does it take to cover one fourth the distance starting from rest at the top?
An object accelerates from rest to a velocity 27.5 m/s in 10 sec. Find the distance covered by the object during next 10 s.
Two trains, one travelling at 15 ms-1 and other at 20 ms-1, are heading towards one another along a straight track. Both the drivers apply brakes simultaneously when they are 500 m apart. If each train has a retardation of 1ms-1, the separation after they stop is
A juggler keeps on moving four balls in the air throwing the balls after regular intervals. When on ball leaves his hand (speed = 20 ms-1) the position of other balls (height in m) will be (take g = 10ms-1)
A particle slides from rest from the topmost point of a vertical circle of radius r along a smooth chord making an angle θ with the vertical. The time of descent is
A parachutist drops first freely from an aeroplane for 10 s and the parachute opens out. Now the escends with a net retardation of 2.5 m/s2. If the bails out of the plane at a height of 2495 m and g = 10 m/s2, his velocity on reaching the ground will be