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An explosion breaks a rock into three parts in a horizontal plane. Two of them go off at right angles to each other. The first part of mass moves with a speed of and the second part of mass moves with speed. If the third part flies off with speed, then its mass is:

  1. A
  2. B
  3. C
  4. D

Solution & Step-by-step Explanation

According to the Law of Conservation of Linear Momentum, the total momentum before and after the explosion must be zero (since the rock was initially at rest).

The magnitude of the third part's momentum must equal the magnitude of the resultant of the first two.Given: Since :

For the third part:

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An explosion breaks a rock into three parts in a horizontal plane. Two of them go off at right angles to each other. The first part of mass moves with a speed of and the second part of mass moves with speed. If the third part flies off with speed, then its mass is:
A
B
C
D

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MechanicsConservation of Momentum

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