Question

What is the potential energy of a stone of mass $ 20 $ kg that is lifted to a height of $ 5 $ m, if $ g = 10Nk{g^{ - 1}} $

Answer 1

Hint: The potential energy of an object can be defined as an energy which is formed due to the height of the acceleration and gravity along with the mass. It is denoted by PE. Here we will place the given values in the formula and simplify for the required value.

Complete step-by-step answer:
Mass, $ m = 20kg $
Height, $ h = 5m $
Gravitational field strength, $ g = 10Nk{g^{ - 1}} $
Potential energy of the stone can be given by,
 $ PE = mgh $
Place the given values in the above expression –
 $ PE = 20(10)(5) $
Simplify the above expression by finding the product of the terms on the right hand side of the equation –
 $ PE = 1000 $ Joules
Hence, the potential energy of a stone of mass $ 20 $ kg that is lifted to a height of $ 5 $ m, is $ 1000 $ Joules.

Note: Always remember that the potential energy of the system can be negative or the positive but kinetic energy and the total energy of the system is always positive. Know the types and differences between the forms of the energy and the correlation among them. Do not forget to write the appropriate unit after the calculation is done. Always check the units of the terms given before placing them in the formula, all the units should be in the same system of units.