Answer:
0.2 J
Explanation:
The pendulum forms a right triangle, with hypotenuse of 50 cm and base of 30 cm. The height of this triangle can be found with Pythagorean theorem:
c² = a² + b²
(50 cm)² = a² + (30 cm)²
a = 40 cm
The height of the triangle is 40 cm. The height of the pendulum when it is at the bottom is 50 cm. So the end of the pendulum is lifted by 10 cm. Assuming the mass is concentrated at the end of the pendulum, the potential energy is:
PE = mgh
PE = (0.200 kg) (9.8 N/kg) (0.10 m)
PE = 0.196 J
Rounding to one significant figure, the potential energy is 0.2 J.
The units used to measure speed and velocity are as follows: m/s, Km/h, and mph.
In longitudinal waves, the particles of the medium or a system displaces back and forth(parallel) in the direction of the propagation of waves. In transverse waves, the particles of the medium or a system displaces perpendicular to the direction of the propagation of waves. Therefore, C is correct.