Question

A bullet moving with 10m/s and brought to rest penetrating the wood plank of 4 cm thick calculate retardation?
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Answer 1

Given:

✭ Bullet is moving with a initial velocity of 10 m/s

✭ It penetrates 4 cm on a plank and then comes to rest

To Find:

◈ The retardation?

Solution:

Concept

So here we may first convert the distance from cm to m, then we shall use the third equation of motion to find the acceleration, here retardation of the body!!

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On converting distance from cm → m

➝ 1 cm = 100 m

➝ 4 cm = 4/100

➝ Distance = 0.04 m

So then as per the third equation of motion,

v²-u² = 2as

• v = Final Velocity = 0 m/s
• u = Initial Velocity = 10 m/s
• a = Acceleration = ?
• s = Distance = 0.04 m

Substituting the values,

➳ v²-u² = 2as

➳ 0²-10² = 2×a×0.04

➳ 0-100 = 0.08a

➳ -100 = 0.08a

➳ -100/0.08 = a

➳ Acceleration = -1250 m/s²

Therefore the retardation will be 1250 m/s²

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☯ Know More

✪ v = u+at

✪ s = ut+½at²

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Answer 2

what is the meaning of pasture