Question

A body of mass M at rest explodes into three pieces, in the ratio of masses 1 : 1 : 2. Two smaller pieces fly off perpendicular to each other with velocities of 30 ms–1 and 40 ms–1 respectively. The velocity of the third piece will be

• A. 15 ms–1
• B. 25 ms–1
• C. 35 ms–1
• D. 50 ms–1

Answer 1

Answer: (B)

25 ms–1

Answer 2

The correct option is(B): 25 m/s.

Conserving momentum:

$m(30\^{i})+m(40\^{i})+2m(\overrightarrow{v})=(\overrightarrow{0})$

$⇒(\overrightarrow{v})=-15\^{i}-20\^{i}$

$⇒(\overrightarrow{v})=25m/s$