Momentum of a Pendulum: Angular and Linear Changes

  • Thread starter Thread starter Timothy Schablin
  • Start date Start date
  • Tags Tags
    Momentum Pendulum
AI Thread Summary
A pendulum's linear and angular momentum change as it swings due to the influence of gravity, which increases its velocity. The magnitude of momentum varies as the pendulum moves along its arc, while the direction of momentum also shifts, remaining tangential to the path. To analyze these changes, one can apply the conservation of mechanical energy to determine the speed at different points in the swing. By calculating the velocity, the corresponding linear momentum can be established, followed by the determination of angular momentum using its definition. Ultimately, both linear and angular momenta are found to change throughout the pendulum's motion.
Timothy Schablin
Messages
17
Reaction score
0
If a pendulum swings in a given arc, because of gravity acting on it in the vertical direction, does the linear and angular momentums change since it is picking up velocity because of gravity?
 
Physics news on Phys.org
Momentum is a vector. The magnitude of momentum changes because the velocity changes (linear and angular) and the direction of momentum also changes.
 
You can calculate what you are curious about. Use conservation of mechanical energy to calculate the speed at various points in the arc. Since the direction of the velocity is always tangential to the path, you now know the velocity at any point. Then you know the momentum. Now use the definition of angular momentum to find that. Certainly, you will find that both linear and angular momenta change as the pendulum swings.
 
  • Like
Likes person123
The rope is tied into the person (the load of 200 pounds) and the rope goes up from the person to a fixed pulley and back down to his hands. He hauls the rope to suspend himself in the air. What is the mechanical advantage of the system? The person will indeed only have to lift half of his body weight (roughly 100 pounds) because he now lessened the load by that same amount. This APPEARS to be a 2:1 because he can hold himself with half the force, but my question is: is that mechanical...
Hello everyone, Consider the problem in which a car is told to travel at 30 km/h for L kilometers and then at 60 km/h for another L kilometers. Next, you are asked to determine the average speed. My question is: although we know that the average speed in this case is the harmonic mean of the two speeds, is it also possible to state that the average speed over this 2L-kilometer stretch can be obtained as a weighted average of the two speeds? Best regards, DaTario
Some physics textbook writer told me that Newton's first law applies only on bodies that feel no interactions at all. He said that if a body is on rest or moves in constant velocity, there is no external force acting on it. But I have heard another form of the law that says the net force acting on a body must be zero. This means there is interactions involved after all. So which one is correct?
Back
Top