When a ball hits a wall with a velocity of 50m/s and bounces back with the same speed, what is the change in velocity of the ball?

A police van moving on a highway with a speed of 30 km h_ 1 fires a bullet at a thief’s car speeding away in the same direction with a speed of 192 km h^-1 . If the muzzle speed of the bullet is 150 m s^1 with what speed does the bullet hit the thief’s car ? (Note: Obtain that speed which is relevant for damaging the thief’s car).

Two train 100 m and 89 m in length are running in opposite directions with a velocity 40 km/hr and 30 km/hr. At what time they will completely cross each other.

Onna two-lane road, car A is travelling with a speed of 36 km h_1. Two care B and C approach car A in opposite directions with a speed of 54'km h_1 each. vAt a certain instant, when the distance AB is equal to AC, both being 1 km,* B’ decides to overtake A before C does. What minimum acceleration of car B is required to avoid an accident?

A batsman deflects a ball by an angle of 45° without changing its initial speed which is equal to 54 km/h. What is the impulse imparted to the ball? (Mass of the ball is 0.15 kg.)

What will be the wavelength of a ball of mass 0.1 kg moving with a velocity of 10 ms^-1 ?

Two particles, each of mass m and speed v_3 travel in opposite directions along parallel lines separated by a distance d. Show that the vector angular momentum of the two particle system is the same whatever be the point about which the angular momentum is taken.

Two towns A and B are connected by a regular bus service with a bus leaving in either direction every T minutes. A man cycling with a speed of 20 km h~1 in the direction A to B notices that a bus goes past him every 18 min in the direction of his motion, and every 6 min in the opposite direction. What is the period T of the bus service and with what speed - (assumed constant) do the buses ply on the road?

Two objects, each of mass 1.5 kg, are moving in the same straight line but in opposite directions. The velocity of each object is 2.5 m s^-1 before the collision during which they stick together. What will be the velocity of the combined object after collision?

Two cars are moving in the same direction with the same speed ( = 30km/hr ). They are separated by a distance of 5 km. What is the speed of a car moving in the opposite direction if it met these cars at an interval of 4 minutes?