I have the question:
"Calculate the total energy of the moving object, when mass = $4$ kg, acceleration due to gravity = $9.81~\text{ms}^{-2}$, height = $10$ m and velocity = $3~\text{ms}^{-1}$"
I know that Total energy = potential energy + kinetic energy.
Therefore, Total energy = $mgh + \frac{1}{2} mv^2$. However, the value for gravity is not given and I do not know how to calculate this using the following information given. I also do not know if my method of solving the problem is correct. The final units I get for total energy is [$\text{kg}^2\text{m}^2\text{s}^{-4}$].
Best Answer
In the potential energy: $E_P=mgh$, $m$ is the mass, $g$ is the acceleration due to gravity and $h$ is the height. So you know all you need and the units of measure are: $$ [mgh]=kg \cdot \frac{m}{s^2}\cdot m =kg \cdot \left(\frac {m}{s} \right)^2 $$ , the same as for the kinetic energy.