Question

A body of mass 60kg is moving with a speed of$50m{{s}^{-1}}$. Find its kinetic energy.

Answer 1

Hint: heat is a form of energy. Energy is the capacity to do the work and energy exists in different forms. From the law of conservation energy can neither be created nor be distorted but it can be transformed to another form. SI unit of energy is joule (J) and energy is a scalar quantity which has only magnitude.

Complete step-by-step solution:
Kinetic energy is the energy that it possesses due to motion. There are many forms of kinetic energy and that are energy due to vibrational motion, energy due to rotational motion and translational.an object that has vertical or horizontal motion has kinetic energy. Kinetic energy is called working energy and kinetic energy is denoted as KE.
Kinetic energy is given by:
\[KE=\dfrac{1}{2}m{{v}^{2}}\] $\cdots \cdots (1)$
Where m=mass of object
              V=speed of object
Kinetic energy of an object is directly proportional to the square of its speed and kinetic energy is a scalar quantity
From the data the value of mass and speed of object are given
 m=60kg and $v=50m{{s}^{-1}}$
Substituting these values in equation (1)
After substitution
\[KE=\dfrac{1}{2}60\times {{(50)}^{2}}\]
\[KE=75000kgm{{s}^{-1}}\]
$KE=7.5\times {{10}^{4}}J$
Kinetic energy of the body is equal to $7.5\times {{10}^{4}}J$.

Note: Kinetic energy is always associated with motion and conservation of energy principle is also called the first law of thermodynamics. There are different types of energy and that is potential or stored, kinetic, thermal, electrical, chemical and nuclear energy. Dimensional formula of energy is $M{{L}^{2}}{{T}^{-2}}$.