Arnab

A 50 g bullet travelling with an initial velocity of 400 m/s penetrates into a wall with an average force of 4*10^4 N.It goes out of the wall with a velocity of 50 m/s. What is the thickness of the wall

4.QR Because log(x) is dimensionless. Here (x)=(Qx+Rt) So [Q][x]=[M^0][L^0][T^0] So [Q]=[L^-1] Then [R]=[T^-1] & [P]=[L] ( Same as dimension of y= displacement) Then the only answer is QR which have different dimension from the other three options.

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