Package A Races Down the Ramp: How Long Does it Take?

  • Thread starter Thread starter mags
  • Start date Start date
  • Tags Tags
    Ramp
AI Thread Summary
To determine how long it takes for Package A to reach the bottom of a 20-degree ramp, one must consider its mass of 5.0 kg and a coefficient of friction of 0.20. The gravitational force acting on the package can be resolved into components, allowing for the calculation of the net downward force after subtracting friction. This net force divided by the mass provides the acceleration of Package A. Using kinematic equations, the time required to travel the ramp's length can then be calculated. The discussion raises a question about whether Package B influences Package A's acceleration, but the primary focus remains on Package A's motion down the ramp.
mags
Messages
5
Reaction score
0
Two packages at UPS start sliding down the 20 degree ramp.Package A has a mass of 5.0kg and a coefficient of friction of 0.20. Package B has a mass of 10 kg and a coefficient of 0.15. how long does it take package A to reach the bottom?

http://img362.imageshack.us/my.php?image=knightfigure0825pe6.jpg
 
Physics news on Phys.org
The question isn't very clear; does package B push on package A and help it accelerate?
 
that's all I'm given...
 
tan(20) =0.36 > 0.2, so the sliding that just started will continue.
So resolve the mass into a normal and a downward (along the slide) component.
Subtract the frictional force will give you the downward force.
Dividing the force by the mass gives the acceleration.
Use the usual formulae for acceleration as a function of distance and speed to find the time required to travel the down ramp of length L.
 
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