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A 0.5 kg basketball moving 5 m/s to the right collides with a 0.05 kg tennis

ball moving 30 m/s to the left. After the collision, the tennis ball is moving 34
m/s to the right. What is the velocity of the basketball after the collision?
Assume an elastic collision occurred.
A. 1.4 m/s to the left
B. 1.4 m/s to the right
C. 11.4 m/s to the right
D. 11.4 m/s to the left

SOMEBODY HELP ME

User Vaku
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2 Answers

4 votes

Answer:

A. 1.4 m/s to the left

Step-by-step explanation:

User Gophermofur
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4 votes

Answer:

A. 1.4 m/s to the left

Step-by-step explanation:

To solve this problem we must use the principle of conservation of momentum. Let's define the velocity signs according to the direction, if the velocity is to the right, a positive sign will be introduced into the equation, if the velocity is to the left, a negative sign will be introduced into the equation. Two moments will be analyzed in this equation. The moment before the collision and the moment after the collision. The moment before the collision is taken to the left of the equation and the moment after the collision to the right, so we have:


M_(before) = M_(after)

where:

M = momentum [kg*m/s]

M = m*v

where:

m = mass [kg]

v = velocity [m/s]


(m_(1) *v_(1) )-(m_(2) *v_(2))=(m_(1) *v_(3) )+(m_(2) *v_(4))

where:

m1 = mass of the basketball = 0.5 [kg]

v1 = velocity of the basketball before the collision = 5 [m/s]

m2 = mass of the tennis ball = 0.05 [kg]

v2 = velocity of the tennis ball before the collision = - 30 [m/s]

v3 = velocity of the basketball after the collision [m/s]

v4 = velocity of the tennis ball after the collision = 34 [m/s]

Now replacing and solving:

(0.5*5) - (0.05*30) = (0.5*v3) + (0.05*34)

1 - (0.05*34) = 0.5*v3

- 0.7 = 0.5*v

v = - 1.4 [m/s]

The negative sign means that the movement is towards left

User JLeonard
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