MCQ
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$a_1=2 a_2$
- ✓$a_2=2 a_1$
- C$a_1=a_2$
- DData insufficient
