A pendulum is made with a 4.00 kg mass suspended at the end of a 75.0 cm thin rod.The pendulum is started at an angle of 20.0 degrees with the vertical.What is the velocity of the pendulum as it passes through the origin?
A) 98.9 cm/s
B) 94.2 cm/s
C) 89.2 cm/s
D) 82.1 cm/s
E) 79.5 cm/s

Question

Quizplus · Accepted Answer

The potential energy at the start is converted to kinetic energy at the lowest point. Using conservation of energy: mgh = 0.5mv^2. The height h can be found using h = L(1 - cos(θ)), where L is the length of the pendulum and θ is the angle. Solving for v gives approximately 94.2 cm/s.

A Pendulum Is Made with a 4