CBSE
Gujarat Board
Haryana Board
Class 10
Class 12
A 0.5 kg ball moving with a speed of 12 m/s strikes a hard wall at an angle of 30Â° with the wall. It is reflected with the same speed and at the same angle. If the ball is in contact with the wall for 0.25 s, the average force acting on the wall is
48 N
24 N
12 N
96 N
B.
24 N
The vectorÂ Â represents the momentum of the object before the collision, and the vectorÂ Â that after the collision. The vectorÂ Â represents the change in momentum of the objectÂ .
As the magnitudes of Â Â are equal, the components ofÂ Â along the wall are equal and in the same direction, while those perpendicular to the wall are equal and opposite. Thus, the change in momentum is due only to the change in direction of the perpendicular components.
Hence, Â
Â Â Â Â Â Â Â Â Â Â Â
Its time rate will appear in the form of average force acting on the wall.
Â
Â Â
The vectorÂ Â represents the momentum of the object before the collision, and the vectorÂ Â that after the collision. The vectorÂ Â represents the change in momentum of the objectÂ .
As the magnitudes of Â Â are equal, the components ofÂ Â along the wall are equal and in the same direction, while those perpendicular to the wall are equal and opposite. Thus, the change in momentum is due only to the change in direction of the perpendicular components.
Hence, Â
Â Â Â Â Â Â Â Â Â Â Â
Its time rate will appear in the form of average force acting on the wall.
Â
Â Â