Answer:



Explanation:
<u>Simple Pendulum</u>
It's a simple device constructed with a mass (bob) tied to the end of an inextensible rope of length L and let swing back and forth at small angles. The movement is referred to as Simple Harmonic Motion (SHM).
(a) The angular frequency of the motion is computed as

We have the length of the pendulum is L=0.81 meters, then we have


(b) The total mechanical energy is computed as the sum of the kinetic energy K and the potential energy U. At its highest point, the kinetic energy is zero, so the mechanical energy is pure potential energy, which is computed as

where h is measured to the reference level (the lowest point). Please check the figure below, to see the desired height is denoted as Y. We know that

And

Solving for Y



The potential energy is


The mechanical energy is, then


(c) The maximum speed is achieved when it passes through the lowest point (the reference for h=0), so the mechanical energy becomes all kinetic energy (K). We know

Equating to the mechanical energy of the system (M)

Solving for v


Light energy is defined as how nature moves energy at an extremely rapid rate, and it makes up about 99% of the body's atoms and cells, and signal all body parts to carry out their respective tasks. An example of light energy is the movement of a radio signal.
C. It depends on the medium
Answer:
Thermal/Heat energy, kinetic energy, light energy, & Electromagnetic energy