Answer:
u= 755 m/s
Explanation:
Lets take
Velocity of bullet = u m/s
The velocity of system after collision ,v= 5 m/s
m= 10 g = 0.01 kg
M= 1.5 kg
From linear momentum conservation( because there is no any external force on the system)
Pi= Pf
m u = ( m +m) v
0.01 x u= (1.5 + 0.01) x 5
u= 755 m/s