A 28 g bullet pierces a sand bag 30 cmthick. If the initial bullet velocity was 55m/s and it emerged from the sandbag with18 m/s what is the magnitude of the frictionforce (assuming it to be constant) the bullet experienced while ittraveled through the bag?
a. 130 N
b. 1.3 N
c. 13 N
d. 38 N

Here not any option is matching but only (A) option is near to our answer.

The frictional force is 126.046 N

Explanation:

Given:

Mass of bullet kg

Thickness of sand bag m

Initial bullet velocity

Final bullet velocity

According to the work energy theorem,

Work done by friction force is equal to change in kinetic energy.

Here we have to find friction force

  N

Here not any option is matching but only (A) option is near to our answer.

Therefore, the frictional force is 126.046 N

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