A bullet is fired into a huge wooden block . The bullet whilemoving insidethe blockloses half the velocity when it travles 6 cm inside the block . hOe far , then would it go inside the block ? And becomes rest .

A bullet is fired into a huge wooden block . The bullet whilemoving in

1.	A bullet is fired into a huge wooden block . The bullet whilemoving insidethe blockloses half the velocity when it travles 6 cm inside the block . hOe far , then would it go inside the block ? And becomes rest .
Answer» Solution :Suppose the intial kinetic energy of bullet` = 1/2 mv_(0)^(2)` when the velocity becomes halved the KINETICENERGY= `1/2 ((mv_(0)^(2))/4)` According to WORK energy theorem , `W = DeltaK = K - K_(0)` ` :. F.d =1/2 ((mv_(0)^(2))/4)-1/2mv_(0)^(2)` ` :. F(6) =1/2 mv_(0)^(2) (1/4-1)` `F(6) =-3/8 mv_(0)^(2)` ` :. F = - 1/16 mv_(0)^(2)` If before coming to rest travels an additional DISTANCE d . Its kinetic energy becomes zero . ` :. Deltak =W` ` :. 0 -(mv_(0)^(2))/8 =[Fd] =-1/16 mv_(0)^(2) d` ` :. d = 2 cm `