A target is made of two plates, one of wood and other of iron. thickness of wooden plate is 4,cm and

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2.Motion in Straight Line

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A target is made of two plates, one of wood and the other of iron. The thickness of the wooden plate is $4\,cm$ and that of iron plate is $2\,cm$. A bullet fired goes through the wood first and then penetrates $1\,cm$ into iron. A similar bullet fired with the same velocity from opposite direction goes through iron first and then penetrates $2\,cm$ into wood. If $a_1$ and $a_2$ be the retardations offered to the bullet by wood and iron plates respectively, then

A$a_1=2 a_2$

B$a_2=2 a_1$

C$a_1=a_2$

DData insufficient

Solution

(b)
$0=u^2-2 a_1(4)-2 a_2(1)$
$0=u^2-2 a_2(2)-2 a_1(2)$
From these two equations, we get,
$a_2=2 a_1$

Standard 11

Physics

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