Mechanics- connected particles

  • Context: MHB 
  • Thread starter Thread starter Shah 72
  • Start date Start date
  • Tags Tags
    Mechanics Particles
Click For Summary
SUMMARY

The discussion focuses on solving mechanics problems involving connected particles and pulleys. Participants emphasize the importance of understanding the role of tension in the connecting string and the necessity of setting up net force equations for each mass. Key equations discussed include \( F = m \times a \) and specific force equations for both the mass on the incline and the mass on the horizontal floor. The calculated acceleration for the floor mass is determined to be \( 1.2 \, \text{m/s}^2 \), with the speed of box B also calculated as \( 1.2 \, \text{m/s} \).

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Familiarity with kinematics equations
  • Knowledge of tension in strings and pulleys
  • Basic concepts of friction and inclined planes
NEXT STEPS
  • Study the derivation and application of Newton's second law in multi-body systems
  • Learn how to apply kinematics equations to determine acceleration and velocity
  • Explore the effects of friction on inclined planes and connected systems
  • Practice solving problems involving pulleys and connected masses
USEFUL FOR

Students studying physics, particularly those focusing on mechanics, as well as educators and tutors looking for examples of problem-solving strategies in connected particle systems.

Shah 72
MHB
Messages
274
Reaction score
0
20210531_213908.jpg

I have no clue how to do this. Pls help
 
Mathematics news on Phys.org
The pulleys only act to change the direction of the tension in the connecting string.

It should be obvious that the mass on the incline slides down the inline, making the mass on the horizontal floor move left … no way the system moves otherwise.

Set up two net force equations like the ones I’ve set up previously, one for each mass.

You need to start taking ownership of these problems.
 
skeeter said:
The pulleys only act to change the direction of the tension in the connecting string.

It should be obvious that the mass on the incline slides down the inline, making the mass on the horizontal floor move left … no way the system moves otherwise.

Set up two net force equations like the ones I’ve set up previously, one for each mass.

You need to start taking ownership of these problems.
Thank you! The pulley ones are a bit confusing. I need to practice more on these kind of problems.
 
skeeter said:
The pulleys only act to change the direction of the tension in the connecting string.

It should be obvious that the mass on the incline slides down the inline, making the mass on the horizontal floor move left … no way the system moves otherwise.

Set up two net force equations like the ones I’ve set up previously, one for each mass.

You need to start taking ownership of these problems.
 
Last edited:
skeeter said:
The pulleys only act to change the direction of the tension in the connecting string.

It should be obvious that the mass on the incline slides down the inline, making the mass on the horizontal floor move left … no way the system moves otherwise.

Set up two net force equations like the ones I’ve set up previously, one for each mass.

You need to start taking ownership of these problems.
In this
F= m×a
T- 0.2× 20cos 30-10= 2a
T- mu R= 2a.
I still don't understand how to calculate a
 
You are given that it takes 1 second for the floor mass to move 0.6m from rest. You should be able to determine the magnitude of acceleration of the floor mass with that info using a kinematics equation.

Both masses undergo the same magnitude of acceleration.

also,

forces for the mass on the incline ...

$m_1g\sin{\theta} - \mu_1 m_1 g\cos{\theta} - T = m_1a$

mass on the floor ...

$T - \mu_2 m_2g = m_2a$

Tension in the string is the same for both masses.
 
skeeter said:
You are given that it takes 1 second for the floor mass to move 0.6m from rest. You should be able to determine the magnitude of acceleration of the floor mass with that info using a kinematics equation.

Both masses undergo the same magnitude of acceleration.

also,

forces for the mass on the incline ...

$m_1g\sin{\theta} - \mu_1 m_1 g\cos{\theta} - T = m_1a$

mass on the floor ...

$T - \mu_2 m_2g = m_2a$

Tension in the string is the same for both masses.
Thanks a lot. So I get a= 1.2m/s^2 and speed of box B = 1.2m/s
 
skeeter said:
You are given that it takes 1 second for the floor mass to move 0.6m from rest. You should be able to determine the magnitude of acceleration of the floor mass with that info using a kinematics equation.

Both masses undergo the same magnitude of acceleration.

also,

forces for the mass on the incline ...

$m_1g\sin{\theta} - \mu_1 m_1 g\cos{\theta} - T = m_1a$

mass on the floor ...

$T - \mu_2 m_2g = m_2a$

Tension in the string is the same for both masses.
For q(d) tension is zero as the string breaks. So I need to calculate the acceleration for A
2a=10- 0.2× 20 cos 30 , a=3.27 m/s^2, s = 1-0.6= 0.4, v^2=u^2+2as, I get v =2.01m/s
 
  • #10

Similar threads

  • · Replies 9 ·
Replies
9
Views
1K
  • · Replies 4 ·
Replies
4
Views
832
  • · Replies 6 ·
Replies
6
Views
1K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 20 ·
Replies
20
Views
1K
  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 5 ·
Replies
5
Views
1K
  • · Replies 2 ·
Replies
2
Views
1K