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In-s [12.5K]
3 years ago
8

An empty train car of mass 2.0 x 10^4 kg coasts along at 10 m/s. A 3000-kg boulder is suddenly dropped vertically into the car.

Find the speed of the car immediately after the boulder is dropped.
Physics
1 answer:
Zepler [3.9K]3 years ago
8 0

Answer:8.69 m/s

Explanation:

Given

mass of Empty train m=2\times 10^4 kg

velocity of car v=10 m/s

mass of Boulder M=3000 kg

Since no External force is acting therefore conserving Momentum

Train and boulder moves with same velocity after collision

m v=(M+m)v'

2\times 10^4\times 10=(2\times 10^4+3000)v'

v'=\frac{20,000\times 10}{23000}

v'=8.69 m/s

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4 years ago
A 50 kg car is pushed so that it speeds up from 20 m/s to 50 m/s in 3 seconds. What is the force acting on the car?
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A kid at the junior high cafeteria wants to propel an empty milk carton along a lunch table by hitting it with a 3.0g spit ball.
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