Question

A skater with a mass of 72 kg is traveling east at 5.8 m/s when he collides with another skater of mass 45 kg heading 60° south of west at 12 m/s. If they stay tangled together, what is their final velocity?

Answer 1

The final velocity is 5.87 m/s

Explanation:

Given-

mass, $m_{1}$ = 72 kg

speed, $v_{1}$ = 5.8 m/s

$Mass_{2}$,$m_{2}$  = 45 kg

$speed_{2}$,$v_{2}$  = 12 m/s

Θ = 60°

Final velocity, v = ?

Applying the conservation of momentum:

$m_{1}$ X $v_{1}$ + $m_{2}$ X $v_{2}$ = ($m_{1}$ +$m_{2}$ ) v

72 X 5.8 + 45 X 12 X cos 60° = (72 + 45) v

v = 417.6 + 540 X $\frac{0.5}{117}$

v = 417.6 + $\frac{270}{117}$

v = 5.87 m/s

The final velocity is 5.87 m/s