Physics-
General
Easy
Question
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 2cm into wood. If 
and 
be the retardation offered to the bullet by wood and iron plates respectively, then
- Data insufficient
The correct answer is:
Let and be the retardations offered to be bullet by wood and iron respectively.
For 
and 
Adding, we get
(i)
For 
and 
Adding, we get
(ii)
Equating Eqs. (i) and (ii) and solving, we get
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