How to Calculate Speed Using Kinematic Equations and Conservation of Momentum

1A. A 5.3 kg ball is falling to the ground. When it is at height 80.6 m, it has speed 11.5 m/s. What is the speed of the ball when it drops to 37.6 m?

What is the formula for speed and how can kinematic equations be used to calculate the speed of the falling ball?

1B. Billiard ball A (having mass 4.2 kg) sits at rest. Billiard ball B (also having mass 4.2 kg) is moving towards A at a speed of 15.2 m/s. After the two collide, Billiard Ball B is moving in the opposite direction at

How can conservation of momentum be applied to calculate the speed of Billiard Ball A after the collision?

1C. Billiard Ball A has mass 2.1 kg and is moving to the right at 29.8 m/s. Billiard ball B has mass 3.0 kg and is moving to the left at 9.0 m/s. If, after the collision, Billiard Ball A is still moving to the right at 5.6 m/s, then at what speed is Billiard Ball B also moving to the right?

How can conservation of momentum be used to determine the speed at which Billiard Ball B is moving to the right after the collision?

Answer:

Speed is the ratio of distance traveled to the time taken. The formula for speed is distance traveled divided by time taken. The kinematic equation v^2 = u^2 + 2as can be used to calculate the speed of the falling ball.

For the falling ball scenario, the speed of the ball when it drops from 37.6 m is u = 31.23 m/s.

In the case of the billiard balls, conservation of momentum can be applied to calculate the speeds after the collision. For Billiard Ball A and Ball B scenario, the speed of Ball A after the collision is 15.2 m/s.

Similarly, for the Billiard Ball A and Ball B moving in opposite directions scenario, the speed of Ball B moving to the right after the collision is 3.92 m/s.

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