Answer:
The kinetic energy of the pendulum at the lowest point is 0.393 joules.
Explanation:
Under the assumption that effects from non-conservative forces can be neglected, the maximum kinetic energy of the pendulum (lowest point) ([tex]K_{2}[/tex]), measured in joules, is equivalent to the maximum gravitational potential energy (highest point) ([tex]U_{g,1}[/tex]), measured in joules, by th Principle of Energy Conservation:
[tex]U_{g,1} = K_{2}[/tex] (1)
By the definition of potential gravitational energy and under the assumption that the height of the lowest point is zero, we conclude that the kinetic energy of the pendulum is:
[tex]K_{2} = m\cdot g\cdot y_{2}[/tex] (1b)
Where:
[tex]m[/tex] - Mass of the weight of the pendulum, measured in kilograms.
[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.
[tex]y_{2}[/tex] - Height of the pendulum at highest point, measured in meters.
If we know that [tex]m = 1\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex] and [tex]y_{2} = 0.04\,m[/tex], then the kinetic energy of pendulum at the lowest point:
[tex]K_{2} = (1\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)\cdot (0.04\,m)[/tex]
[tex]K_{2} = 0.393\,J[/tex]
The kinetic energy of the pendulum at the lowest point is 0.393 joules.
