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**1. Homework Statement**

A 10g bullet moving at 300.m/s hits and passes through a 2.20kg pendulum target. After the impact, the 1.20m long pendulum rises up to an angle of 15 degree, find the final speed of the bullet.

**2. Homework Equations**

Ek= 1/2MV^2

Ep= MGH

Momentum = MV

**3. The Attempt at a Solution**

I assumed all energy before and after the question will be = because the collision is inelastic, both masses dont stay together. I found the height the pendulum rises by doing 1.2-(1.2Cos15). Then I put everything i knew in EK= Ep + EK

(300^2)*(0.01)*(0.5) = (2.20)(9.8)(0.04) + (0.5)(0.01)(v')^2

When I solve for velocity I get the answer wrong. What am I doing wrong, am I wrong that energy is conserved ?