Two bodies of masses 8 kg and 5 kg travelling in the same direction with speeds x m/s and 2 m/s respectively collide. If after collision, they move together with a speed of 3.85 m/s, find, correct to the nearest whole number, the value of x.
2
5
8
13
Correct answer is B
\((m_{1} v_{1} + m_{2} v_{2}) = (m_{1} + m_{2})v\) (Inelastic momentum)
\(8x + (5 \times 2) = (8 + 5) \times 3.85\)
\(8x + 10 = 13 \times 3.85 = 50.05\)
\(8x = 50.05 - 10 = 40.05\)
\(x \approxeq 5 m/s\)