Question

A 15 g bullet is fired at 650 m/s into a 4.7 kg block that sits at the edge of a 80-cm-high table. The bullet embeds itself in the block and carries it off the table. How far from the point directly below the table's edge does the block land?

Answer 1

Given:

Mass of the bullet,

Initial velocity of the bullet,

mass of the block,

Initial velocity of the block,

Initial height of the block,

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Consider the bullet and the block

During collision momentum is conserved

Initial momentum = Final momentum

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Find the time of flight of the bullet-block system

The bullet-block system leaves the tabletop horizontally

So initial vertical velocity,

Consider the vertical motion of the bullet-block system

Use formula

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Consider the horizontal motion of the bullet-block system

There is no acceleration in horizontal direction, so horizontal velocity remains constant.

Horizontal velocity = Horizontal Distance/Time of flight

The bullet-block system leaves the tabletop horizontally, so

ANSWER:

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