A 100g of iron nail is hit by a 1 . 5kg hammer striking at a...

If we heat-up an object, then, the energy is used to either change the temperature of the body or to change the state of the body.
If it changes the temperature, then,

$Q = mS ∆ T$
where, $Q$ is the heat given, $m$ is the mass and $∆ T$ is the change in temperature.

We know that a moving object has an energy in the form of kinetic energy, i.e.,
$KE = \dfrac{1}{2}m{v}^{2}$

When that moving object strikes another object, it loses some energy which changes into the heat energy and this heat energy increases the temperature of the object.
Given a hammer of $1 . 5kg$ is moving with $60m{s}^{- 1}$.
Kinetic energy $= \dfrac{1}{2}m{v}^{2} = \dfrac{1}{2} ( 1 . 5 ) ( 60{)}^{2} = 2700J$
One-fourth of kinetic energy changes into heat energy.
$⇒ \dfrac{1}{4} ( KE ) =$ Heat energy
$⇒ \dfrac{1}{4} ( KE ) = m ( S ) ( ∆ T )$
$⇒ \dfrac{1}{4} ( 2700 ) = ( 100 ) ( 0 . 42 ) ( ∆ T )$
$⇒ ∆ T = 16 . 07 ° C$