What is the acceleration of the block up the ramp?

In summary, a large block with a mass of 1400kg is being dragged up a ramp at an angle of 15 degrees by a smaller block with a mass of 530kg falling due to gravity over a pulley. The coefficient of kinetic friction between the large block and the ramp is 0.13. The acceleration of the block up the ramp is determined by the net force acting on it, which is equal to the force of gravity on the smaller block minus the force of gravity on the large block plus the force of friction. This results in a positive acceleration of approximately 2m/s^2.
  • #1
PTPM93
4
0

Homework Statement



A large block is being dragged up a ramp by a block falling due to gravity over a pulley. The large block has a mass of 1400kg and the smaller block suspended has a mass of 530kg. The coefficient of kinetic friction between the large block and the ramp is 0.13. The ramp is at an angle of 15degrees
what is the acceleration of the block up the ramp?

Homework Equations


F=ma
Ff=ukN

The Attempt at a Solution


I know there are four forces actnig on the block, and these are:
in the negative x direction there is the mass of the big block * gravity *sin15 + Ff (m*g*sin15 + 0.13*m*g*cos15)
and in the positive x direction there is the smaller block pulling it down via gravity so m*g*sin15 (m in this case is the smaller block)
a=fnet/m where fnet= mlittle*g*sin15 -(mbig*g*sin15 + 0.13*mbig*g*cos15)
The problem is it ends up being negative when I go to do, and I'm sure the block is mean to be accelerating up the ramp.
a=Fnet/m
 
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  • #2
PTPM93 said:

Homework Statement



A large block is being dragged up a ramp by a block falling due to gravity over a pulley. The large block has a mass of 1400kg and the smaller block suspended has a mass of 530kg. The coefficient of kinetic friction between the large block and the ramp is 0.13. The ramp is at an angle of 15degrees
what is the acceleration of the block up the ramp?

Homework Equations


F=ma
Ff=ukN


The Attempt at a Solution


I know there are four forces actnig on the block, and these are:
in the negative x direction there is the mass of the big block * gravity *sin15 + Ff (m*g*sin15 + 0.13*m*g*cos15)
and in the positive x direction there is the smaller block pulling it down via gravity so m*g*sin15 (m in this case is the smaller block)
a=fnet/m where fnet= mlittle*g*sin15 -(mbig*g*sin15 + 0.13*mbig*g*cos15)
The problem is it ends up being negative when I go to do, and I'm sure the block is mean to be accelerating up the ramp.
a=Fnet/m

It seems like you have a whole lot of forces jumbled up there. Since no loss due to friction was stipulated for the pulley, I think you can consider the whole force due to gravity of the weight is acting parallel to and up along the ramp. Now work on the friction.
 
  • #3
This is what I've figured out so far but I don't think I'm getting the right answer
5yhgsg.jpg
 
  • #4
I seem to be getting ~-2ms^-2 as the acceleration and it should be positive??
I don't understand what I'm doing wrong I have
Net F = ma
Fbigblock = m*g*sin theta - (M*g*sin theta + 0.15 *M * g * cos theta)
.'. a = m*g*sin theta - (M*g*sin theta + 0.15 *M * g * cos theta) divided by M
But it doesn't seem right
 
  • #5
PTPM93 said:
This is what I've figured out so far but I don't think I'm getting the right answer
5yhgsg.jpg

Attached is diagram of what I said before. The smaller weight merely supplies a constant force along the slope of the ramp. You've made the problem harder than it is.
 

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  • #6
Ah okay, Thanks a lot I understand now
 

1. What is the purpose of dragging a block up a ramp?

The purpose of dragging a block up a ramp is to apply a force to the block in a specific direction, causing it to move along the ramp. This can be used to demonstrate principles of friction, gravity, and motion.

2. How does the angle of the ramp affect the block being dragged?

The angle of the ramp affects the amount of force needed to drag the block up the ramp. A steeper angle will require more force to overcome the force of gravity, while a shallower angle will require less force.

3. What factors affect the friction between the block and the ramp?

The amount of friction between the block and the ramp is affected by the materials of the block and ramp, the roughness of their surfaces, and the force applied to the block. Friction can also be affected by the presence of lubricants or other substances between the block and the ramp.

4. How does the weight of the block impact its movement up the ramp?

The weight of the block affects the force of gravity acting on it, which in turn affects the amount of force needed to move the block up the ramp. A heavier block will require more force to overcome the force of gravity and move up the ramp.

5. What are some real-life applications of dragging a block up a ramp?

Dragging a block up a ramp can be used in practical applications such as moving heavy objects, loading and unloading trucks, and construction projects. It can also be used in physics experiments to demonstrate principles of force, motion, and energy.

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