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Stella [2.4K]
2 years ago
6

Two boys on skateboards are facing each other. They push off, the first boy (mass: 43.8 kg) traveling backward at 2.1 m/s. If th

e second boy is now traveling at 3.09 m/s, what is his mass?
Physics
1 answer:
slega [8]2 years ago
5 0

Answer:

The mass of the second boy is, m = 29.77 kg

Explanation:

Given data,

The mass of first boy, M = 43.8 kg

The velocity of first boy, V = -2.1 m/s

The velocity of second boy, v = 3.09 m/s

Then mass of second boy, m = ?

According to the law of conservation of momentum,

                                    mv + MV = 0

                                     m = - MV / v

Substituting the values,

                                     m = 43.8 x 2.1 / 3.09

                                      m = 29.77 kg

Hence, the mass of the second boy is, m = 29.77 kg

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