Solving Two Worlds Spinning: Calculating Tension (T) in String

  • Thread starter Thread starter soupastupid
  • Start date Start date
  • Tags Tags
    Spinning
Click For Summary
SUMMARY

The discussion focuses on calculating the tension (T) in a string connecting two masses, m_a and m_b, with m_b moving upwards at velocity v. The relevant equations include T = m((u^2)/r) and a = (v^2)/R, where u represents linear speed and r is the radius of motion. The initial kinetic energy of m_b is calculated as 0.5(m_b)v^2, which is crucial for understanding the energy dynamics in the system. Participants emphasize applying Newton's 2nd law to analyze the motion of mass B, which is in pure rotation about mass A.

PREREQUISITES
  • Understanding of Newton's 2nd law of motion
  • Familiarity with rotational motion concepts
  • Knowledge of kinetic energy calculations
  • Basic grasp of tension in strings and forces in a system
NEXT STEPS
  • Study the application of Newton's 2nd law in rotational dynamics
  • Learn about the relationship between linear speed and angular velocity
  • Explore energy conservation principles in mechanical systems
  • Investigate tension calculations in various physical scenarios
USEFUL FOR

Students studying physics, particularly those focusing on mechanics and rotational motion, as well as educators seeking to enhance their teaching methods in these topics.

soupastupid
Messages
34
Reaction score
0

Homework Statement



There are two balls with masses m_a and m_b connected by a string. m_b is moving at a velocity v upwards (perpendicular to the string) and it asks for the Tension (T) in the string.

Homework Equations



a=(v^2)/R
delta Energy of system = 0

T = m((u^2)/r)
u is linear speed of rotational motion
r = radius of motion

The Attempt at a Solution



The initial kinetic energy of m_b = .5(m_b)v^2

and that's as far as I got.
Is mass B moving?

how do I start this problem?
 

Attachments

  • two worlds.JPG
    two worlds.JPG
    44.9 KB · Views: 397
Physics news on Phys.org
soupastupid said:

Homework Equations



a=(v^2)/R
That will come in handy.
The initial kinetic energy of m_b = .5(m_b)v^2
Why did you calculate the energy?

and that's as far as I got.
Is mass B moving?
Mass B's velocity is described in the problem statement.

Hint: Viewed from the inertial lab frame, mass B is in pure rotation about mass A (at the instant shown). Apply Newton's 2nd law.
 

Similar threads

Replies
6
Views
2K
  • · Replies 15 ·
Replies
15
Views
3K
Replies
7
Views
4K
Replies
18
Views
5K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 4 ·
Replies
4
Views
2K
Replies
21
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
5
Views
3K
  • · Replies 21 ·
Replies
21
Views
9K