Question

A bullet is fired toward a block of wood (m₁ = 1.17 kg) sitting on a frictionless surface. The bullet has a mass m_b = 30 g, and its initial velocity is 320 m/s in the +x-direction. The bullet embeds itself inside the block of wood. Then the block of wood (with bullet) collides with another block of wood (m₂ = 1.20 kg). The collision is elastic. The first block moves off at an angle of -45^o with respect to +x, while the second block moves off at an angle of +30^o with respect to +x.

a) Write down the momentum equation for the bullet-block collision (using the variables m_b for mass of bullet, m₁ for the mass of the block of wood, v_o for the initial velocity of the bullet, and v_pc for the post collision velocity of the bullet-block combo.) DO NOT FILL IN THE NUMBERS – just write out the algebraic equation.

b) Find the post collision velocity of the first block of wood + bullet right after the collision.

c) Write down the momentum equation for the bullet-block combo collision with the second block, again using the variables listed in part a, as well as using m₂ for the mass of block 2, v_f1 as the final velocity of block 1 (+bullet), and v_f2 as the final velocity of block 2. AGAIN DO NOT FILL IN THE NUMBERS – just write out the algebraic equation.

d) Find the final velocity of block 1 (+bullet), remembering to express it as a number and the angle.

e) Find the final velocity of block 2, remembering to express it as a number and the angle.

Answer 1