(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A bullet of mass 50 g is fired from below into the bob of mass 450 g of a long simple pendulum. The bullet remains inside the bob and the bob rises through a height of 1.8 m. Find the speed of the bullet. Take g=10

2. Relevant equations

Momentum remains conserved

Energy remains conserved

3. The attempt at a solution

I tried to solve this using two methods and thereby I got two differnt answers. Tell me where am I wrong.

Using Kinematics:

Let th speed of the bullet be v. Let the velocity after th bullet is embeed is V. by the principle of conservation of linear momnetum:

[tex]V=\frac{(0.05 Kg)v}{0.45+0.05}=\frac{v}{10}[/tex]

Using v^2=u^2+2ax

v=60 m/s

2nd method:

Momentum remains conserved

Energy remains conserved

Kinetic energy of the bullet =change in potential energy of the bullet bob system.

0.5*0.05*v^2=0.5*10*1.8

[tex]v=\sqrt{360}[/tex]

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# Homework Help: Principles of Conservation

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