How many radians does the cylinder rotate in the first 5.0 seconds?

  • Thread starter jy1231
  • Start date
  • Tags
    Dynamics
In summary, a solid cylinder of mass 10 kg is pivoted and has two ropes wrapped around it, one exerting a force of 5.0 N to the right and the other exerting a force of 6.0 N downward. The net torque is 2 N*m in the clockwise direction, but the angular acceleration cannot be found without knowing the moment of inertia.
  • #1
jy1231
2
0
1. Homework Statement

A solid cylinder of mass 10 kg is pivoted about a frictionless axis through the center O. A rope wrapped around the outer radius R1 = 1.0 m, exerts a force F1 = 5.0 N to the right. A second rope wrapped around another section of radius R2 = 0.50 m exerts a force F2 = 6.0 N downward. How many radians does the cylinder rotate through in the first 5.0 seconds, if it starts from rest?

2. Homework Equations
3. The Attempt at a Solution

I did find the torque for each force, with the counterclockwise force being positive.

so

T(1) = (1.0 m)(5m) = 5 N*m
T(2) = (0.5 m)(6.0 N) = 3 N*m

so I figured out that the net torque would be 2 N*m in the clockwise direction.

But i don't know what to do with this.

Thank you so much!

Sorry, here's the picture: http://tinypic.com/view.php?pic=otlszm&s=7
 
Last edited:
Physics news on Phys.org
  • #2
Find the angular acceleration from another formula for torque (which also requires the moment of inertia)
 
  • #3
jy1231 said:
1. Homework Statement

A solid cylinder of mass 10 kg is pivoted about a frictionless axis through the center O. A rope wrapped around the outer radius R1 = 1.0 m, exerts a force F1 = 5.0 N to the right. A second rope wrapped around another section of radius R2 = 0.50 m exerts a force F2 = 6.0 N downward. How many radians does the cylinder rotate through in the first 5.0 seconds, if it starts from rest?

Hmm. Was there a diagram to accompany this problem? How are we to know if the ropes are wrapped in the same direction?
 

Related to How many radians does the cylinder rotate in the first 5.0 seconds?

What is circular/rotational dynamics?

Circular/rotational dynamics is the study of motion and forces in objects that rotate or move in a circular path. It involves understanding concepts such as angular velocity, centripetal force, and torque.

What is the difference between linear and circular/rotational motion?

Linear motion is movement in a straight line, while circular/rotational motion involves movement along a circular path. Linear motion is described by displacement, velocity, and acceleration, while circular/rotational motion is described by angular displacement, angular velocity, and angular acceleration.

What is centripetal force and how does it relate to circular/rotational motion?

Centripetal force is the force that acts towards the center of a circular path, keeping an object moving in a circular motion. In circular/rotational dynamics, centripetal force is necessary to maintain the object's circular motion and is equal to the mass of the object multiplied by its centripetal acceleration.

What is angular momentum and how is it conserved in circular/rotational motion?

Angular momentum is a measure of an object's rotational motion and is equal to the product of its moment of inertia and angular velocity. In circular/rotational motion, angular momentum is conserved, meaning that it remains constant unless an external torque is applied.

What are some real-world applications of circular/rotational dynamics?

Circular/rotational dynamics has many applications in everyday life, such as in the design and operation of amusement park rides, the motion of planets and satellites in space, and the functioning of machinery and tools that involve rotational motion.

Similar threads

  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
10
Replies
335
Views
9K
  • Introductory Physics Homework Help
Replies
16
Views
2K
  • Introductory Physics Homework Help
Replies
12
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
19
Views
3K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
3K
  • Introductory Physics Homework Help
Replies
1
Views
2K
Back
Top