Two Blocks attached by a string, on an incline

Click For Summary
SUMMARY

The discussion focuses on solving a physics problem involving two blocks connected by a string on an incline. The masses are mA = 3.00 kg and mB = 1.07 kg, with an incline angle of 38.0°. The acceleration was correctly calculated as 6.03 m/s². However, participants struggled with determining the tension in the string, with confusion surrounding the application of Newton's second law and the summation of forces acting on each block.

PREREQUISITES
  • Understanding of Newton's second law of motion
  • Basic knowledge of forces acting on objects on an incline
  • Ability to draw and interpret free body diagrams
  • Familiarity with gravitational force calculations (g = 9.8 m/s²)
NEXT STEPS
  • Study the application of Newton's second law in multi-body systems
  • Learn how to draw and analyze free body diagrams for inclined planes
  • Explore tension calculations in connected systems
  • Practice problems involving forces on inclined planes with multiple masses
USEFUL FOR

Students studying physics, particularly those focusing on mechanics, as well as educators looking for examples of problem-solving techniques in dynamics involving inclined planes.

stripedcat
Messages
44
Reaction score
0

Homework Statement


In the diagram mA is equal to 3.00 kg and mB is equal to 1.07 kg. The angle of the inclined plane is 38.0°

6sq6bn.png


(a) Find Acceleration: 6.03 m/s^2 (got this part)
(b) Find the tension Tb in the connecting string: Not sure

Homework Equations



(a) a = (F/mA + mB)
(b) t = mA * a? or mB * a? Not sure

The Attempt at a Solution



Obviously my mA * a and mB * a both didn't work, I'm not sure what the formula should be.
 
Physics news on Phys.org
What forces act on each block? Draw yourself a free body diagram for one of the masses. Then by applying Newton's 2nd law, you can solve for the tension.
 
I'm sorry, but... What?

The force that acts on each block is gravity, 9.8 * sin theta. That's how I got acceleration.

T = m(g+a)? But is that mA or mB?
 
stripedcat said:
I'm sorry, but... What?

The force that acts on each block is gravity, 9.8 * sin theta. That's how I got acceleration.
Right, but you left it out in your two formulas for tension.

T = m(g+a)? But is that mA or mB?
Do this. Pick a block. Doesn't matter which. Then find ∑F for that block. Direction matters: call down the incline positive.
 
  • Like
Likes   Reactions: 1 person
Doc Al said:
Right, but you left it out in your two formulas for tension.

Woops, sorry. O_O I missed that.

Do this. Pick a block. Doesn't matter which. Then find ∑F for that block. Direction matters: call down the incline positive.

3 * (9.8 + 6.03) = 47.49

I don't know what the summation F means. Sum of forces on the block?

I usually have practice problems so I can play with them until I figure out how to do them, no such luck on this one.
 
stripedcat said:
I don't know what the summation F means. Sum of forces on the block?
Yes.

Did you pick a block? Which one? What forces act on it? What's their sum?
 

Similar threads

Replies
3
Views
652
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 37 ·
2
Replies
37
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
Replies
4
Views
2K
  • · Replies 21 ·
Replies
21
Views
4K
  • · Replies 3 ·
Replies
3
Views
3K
Replies
21
Views
1K
  • · Replies 1 ·
Replies
1
Views
18K
Replies
6
Views
2K