What is the kinetic energy of a body of mass $1\ kg$ moving with a speed of $2\ m/s$?

Here, mass of the body $m=1\ kg.$

Speed of the body $v=2\ m/s$

The kinetic energy of the body $K=\frac{1}{2}mv^2$

$=\frac{1}{2}\times 1\ kg\times(2\ m/s)^2$

$=\frac{1}{2}\times 4$

$=2\ J$

Therefore, kinetic energy of the body is $2\ J$.