Change in gravitional potential energy at an angle?

Click For Summary

Homework Help Overview

The problem involves a pendulum bob with a mass of 0.23 kg attached to a 1.2 m string, initially positioned at an angle of 30 degrees. The question focuses on determining the change in gravitational potential energy as the bob swings from one point to another, specifically from point A to point B, where the angle changes to 35 degrees.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the relationship between the change in angle and the change in height of the bob, questioning how to utilize the angle in calculations. There is mention of using trigonometric functions to relate the angle to height, although specific methods are not detailed.

Discussion Status

The discussion is ongoing, with participants exploring the use of trigonometry to determine height based on the angle and string length. Some guidance has been offered regarding the application of trigonometric relationships, but no consensus or resolution has been reached.

Contextual Notes

Participants note that the height of the bob is not explicitly given, which adds to the complexity of the problem. The focus remains on deriving necessary values from the provided angle and string length.

flemj
Messages
6
Reaction score
0

Homework Statement



A 0.23kg pendulum bob is attached to a string 1.2 long at an angle of 30 degrees. What is the change in the gravitational potential energy of the system as the bob swings from point A to point B
U=

Homework Equations



.5 mv^2 = mgl
U=E+K


The Attempt at a Solution



in the picture it looks like a string attached to a roof with the ball at rest touching the roof and swinging down to a position 35 degrees below I am just not sure how you use the angle of 35 in the problem
 
Physics news on Phys.org
Can you relate the change in angle to the change in height of the bob?
 
Hootenanny said:
Can you relate the change in angle to the change in height of the bob?

the height isn't given its just the length of the string sorry.
 
flemj said:
the height isn't given its just the length of the string sorry.
I know it isn't given, what I was saying is can you work it out using the angle and the length of the string?
 
Hootenanny said:
I know it isn't given, what I was saying is can you work it out using the angle and the length of the string?

would you do that my x sin theta ?

im just really frustrated with this question
 
flemj said:
would you do that my x sin theta ?
I'm not sure what my is meant to be, but yes you should use trigonometry.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
Replies
15
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
5K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 5 ·
Replies
5
Views
14K
  • · Replies 2 ·
Replies
2
Views
1K