If the mass of an object is 15 kg. Find its weight on the earth?

In physics, mass is a quantitative measure of inertia, which is a fundamental property of all matter. It is, in effect, the resistance that a body of matter provides to a change in its speed or position when a force is applied to it. The smaller the change produced by an applied force, the greater the mass of the body.

Mass, m = 15 g

Acceleration due to gravity, g = 10 m/s²

$\mathrm{Weight} \left(\mathrm{W}\right) = \mathrm{Mass} \left(\mathrm{m}\right)\times \mathrm{Acceleration} \mathrm{due} \mathrm{to} \mathrm{gravity} \left(\mathrm{g}\right)$

Thus, $\mathrm{W} = 15 \mathrm{kg} \times 10 \mathrm{m}/{\mathrm{s}}^2$

$\mathrm{W} = 150 \mathrm{kg}.\mathrm{m}/{\mathrm{s}}^2 = 150 \mathrm{N}$