Question

The speed of the bullet and the beam after the impact is 0.1 m / s or 10 cm / s

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Answer 1

The speed of the bullet and the beam after the impact is 0.1 m / s or 10 cm / s according to the calculation as follows.

DISCUSSION :

Known ;

mb = 100 kg

vp = 1000 m / s

mp = 10 gram = 0.01 kg

Was asked

v '=?

COMPLETION :

 Before colliding, the bullet moves with vp speed while the wooden beam is idle. So vb = 0. Then after colliding with nothing at all, the bullet lodged in a wooden block and moved together.

  mp • vp + mb • vb = (mp + mb) • v '

0.01 • 1000 + 100 • 0 = (0.01 + 100) • v '

  10 + 0 = 100.01v '

  10 = 100.01 v '

  v '= $\frac{10}{100.01}$

  v '= 0.099 m / s

  v '= 0.1 m / s

  So, the speed of the wooden block and the bullet after the impact is 0.1 m / s.