Force Between Masses: Solving Physics Homework Questions

AI Thread Summary
The discussion revolves around solving a physics homework problem involving three blocks on a frictionless surface subjected to a horizontal force. The key questions focus on determining the forces between the blocks with masses of 5.8 kg and 8.3 kg, and between the 3.9 kg and 5.8 kg blocks. Participants emphasize the importance of understanding Newton's second law (F=ma) and suggest creating free body diagrams to visualize the forces acting on each block. They note that since there is no friction, the acceleration of the blocks is uniform and can be calculated using the total mass and applied force. Independent study and collaboration with peers are recommended for better comprehension of the material.
pleasehelpme3
Messages
1
Reaction score
0

Homework Statement



--F-->{3.9kg}{5.8kg}{8.3kg}

Three blocks are in contact with each other
on a frictionless horizontal surface. A 413 N
horizontal force is applied to the block with
mass of 3.9 kg as shown in the figure below.
The acceleration of gravity is 9.8 m/s2 .


d)What is the magnitude of the force between
the block with mass 5.8 kg and 8.3 kg?
Answer in units of N


e)What is the magnitude of the force between
the block with mass 3.9 kg and 5.8 kg?
Answer in units of N




Homework Equations


F=ma
F=9.8m/s^2(m1+m2)

Not quite sure, I have been trying to work with these two but am not having much luck.



The Attempt at a Solution



I am hopelessly lost on this one. My teacher is extremely difficult to understand and physics is really giving me a tough time. Any help would be greatly appreciated! Thanks in advance.
 
Physics news on Phys.org
I your teacher is hard to understand or worse--not a good teacher, you will have to do some independent study to stay afloat. Read your textbook slowly and thoroughly. Work with a classmate if possible. Use this site's learning materials. Find and use internet resources.

What is the acceleration of the group of blocks?
Since there is no friction and these blocks are moving horizontally, the acceleration due to gravity is not relevant.
Can you draw free body diagrams of the individual blocks? If you can, then you are almost done.
 
All the blocks are moving together, like a train, under the influence of the horizontal force.
Using Newton's 2nd law, what are their acceleration?
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top