What was the speed of the bullet before it hit the block?

AI Thread Summary
To determine the bullet's speed before impact, one can use the conservation of momentum and energy principles. The bullet, weighing 2.00 g, embeds itself in a 5.00-kg block, causing the block to swing through an arc of 4.50 degrees. The conservation of energy approach is favored because it simplifies calculations by relating the initial kinetic energy of the bullet to the potential energy of the block at its highest point after the collision. Participants in the discussion emphasize the importance of showing work for clarity and understanding. The problem highlights fundamental physics concepts in momentum and energy conservation.
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Physics HELP!

Homework Statement



A 2.00-g bullet hits and becomes embedded in a 5.00-kg wood block which is hanging from a 1.40-m long string. This causes the block to swing through an arc of 4.50. What was the speed of the bullet before it hit the block?

Homework Equations


The Attempt at a Solution



I tried to set the masses equal to each other and then use cos for 4.50 in an attempt to find v not
 
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You need to show some of your work before we can offer tutorial help -- that's in the PF Rules.

What are two approaches that you could take to this problem? Why is the conservation of total energy approach the easiest?
 

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