A bullet becomes hot on hitting a target. Why?

A lead bullet melts on hitting a fixed target. What will be the minimum speed of the bullet, if it is assumed that the heat produced is retained entirely by the bullet? Initial temperature of the bullet = 47.6^(@)C , specific heat of lead = 0.03 cal cdot g^(-1) cdot^(@)C^(-1) , melting point of lead = 327^(@)C , latent heat of fusion of lead = 6 cal cdot g^(-1) , J = 4.2 xx 10^(7) erg cdot cal^(-1) .

The probabilities for A, B, and C hitting a target are (1)/(3), (1)/(5) and (1)/(4) respectively. If they try together, find the probability of exactly one shot hitting the target.

A lead bullet stopped on hitting an iron plate at a velocity of 300 m cdot s^(-1) . Find out the rise in temperature of the bullet, if the heat evolved is shared equally between the bullet and the plate. Given, J = 4 cdot 2 xx 10^(7) erg cdot cal^(-1) , specific heat of lead = 0.03 cal cdot g^(-1) cdot^(@)C^(-1) .

A can hit a target in 3 out of 4 shots and B can hit the target in 4 out of 5 shots. What is the probability of hitting the target ?

If the probability of hitting a target by a shooter, in any shot is 1/3, then the minimum number of independent shots at the target required by him so that the probability of hitting the target at least once is greater than (5)/(6) is

The probability of a man hitting a target is (1)/(4) . How many times must he fire so that the probability of his hitting the target at least once is greater than (2)/(3) ?

The probability of a bomb hitting a target is 0.2. Two direct hits are necessary to destroy a bridge. If six bombs are aimed at the bridge, find the probability that the bridge is destroyed.

A bullet of mass 80 g strikes a target at 100 cm*s^(-1) . After penetration, its velocity reduces to 50 cm*s^(-1) . How much of its kinetic energy is spent ?