Find the energy in $kWh$ consumed in $10$ hours by four devices of power $500\, W$ each. (in $kWh$)

$A$ freely falling object eventually stops on reaching the ground. What happens to its kinetic energy?

Write an expression for the kinetic energy of an object.

Look at the activities listed below. Reason out whether or not work is done in the light of your understanding of the term 'work'.
$1$. Suma is swimming in a pond.
$2$. $A$ donkey is carrying a load on its back.
$3$. $A$ windmill is lifting water from a well.
$4$. $A$ green plant is carrying out photosynthesis.
$5$. An engine is pulling a train.
$6$. Food grains are getting dried in the sun.
$7$. $A$ sailboat is moving due to wind energy.

Can there be displacement of an object in the absence of any force acting on it?

$A$ person holds a bundle of hay over his head for $30$ minutes and gets tired. Has he done some work or not? Justify your answer.