Answer:
speed = 0.542 m/s
Step-by-step explanation:
Data:
mass, m = 1 kg
acceleration of gravity, g = 9.81 m/(s^2)
height, h = 1.5 cm = 0.015 m
The question missing is:
How fast will the pendulum be moving when it passes through the lowest point of its swing?
At the beginning, the pendulum is not moving so its kinetic energy is equal to zero. Taking the lowest point of the pendulum swing as height zero, then there its potential energy is equal to zero. So in the movement from the released of the pendulum to the lowest point of the swing, potential energy becomes kinetic energy, therefore:
PE = KE
m*g*h = (1/2)*m*v^2
v = √(g*h*2)
v = √(9.81*0.015*2)
v = 0.542 m/s