Asked by srikala
a pendulum consists of a wooden bob of mass m and length l. A Bullet of mass m1 is fired towards the pendulum with a speed v1.the bullet emerges out of the bob with a speed v1/3 and the bob just completes motion along a vertical line ,then v1 is?
Answers
Answered by
drwls
What do you mean by "completes motion along a vertical line" ? Does the bob go straight up and stop?
Answered by
srikala
yes the bob goes straight up and stops
Answered by
drwls
Let Vf be the bob velocity just after the bullet has gone through, before it has started to swing upwards.
(1/2)Vf^2 = 2 g l
(from conservation of energy)
Vf = sqrt (4 g*l) = 2 sqrt(g*l)
Now apply conservation of momentum to the bullet interaction:
m1*v1 = m1*(v1/3) + m*Vf
(2/3)m1*v1 = 2*m*sqrt(g*l)
v1 = 3(m/m1)*sqrt(g*l)
(1/2)Vf^2 = 2 g l
(from conservation of energy)
Vf = sqrt (4 g*l) = 2 sqrt(g*l)
Now apply conservation of momentum to the bullet interaction:
m1*v1 = m1*(v1/3) + m*Vf
(2/3)m1*v1 = 2*m*sqrt(g*l)
v1 = 3(m/m1)*sqrt(g*l)
Answered by
Tron
What if the motion of the bob after collision just complete along a vertical circle??
There are no AI answers yet. The ability to request AI answers is coming soon!