Question

A ballistic pendulum consists of a 3.60 kg wooden block on the end of a long string. From the pivot point to the center‐of‐mass of the block is a distance of 2.80 m. With the pendulum hanging straight down, a rifle bullet of 28.0 g mass moving with a speed of 210 m/s embeds itself into the wood. To what maximum angle does the pendulum (with embedded bullet) swing upward?

Answer 1

Answer:

17.799°

Explanation:

When the bullet hits the block at that time the momentum is conserved

So, initial momentum = final momentum

$P_i=P_f$

So $28\times 10^{-3}\times 210=(3.6+0.028)v_f$

$v_f=1.6207\ m/sec$

Now energy is also conserved

So $\frac{1}{2}\times (3.6+0.028)\times 1.6207^2=(3.6+0.028)\times 9.81\times 2.8(1-cos\Theta )$

$cos\Theta =0.8521So\ \Theta =17.799^{\circ}$