Work & Friction: Solve for Force, Work, & Speed

  • Thread starter Thread starter lostinthespiral
  • Start date Start date
  • Tags Tags
    Friction Work
AI Thread Summary
The discussion centers on understanding the relationship between work, friction force, and speed in a physics problem involving a 16.1 kg block being dragged across a rough surface. The user has calculated the work done by a constant force of 118 N to be approximately 8405.82 J but is struggling to find the work done by friction and the block's final speed. The coefficient of kinetic friction is given as 0.228, and the user is encouraged to apply the work-energy theorem to find the net work done on the block. Additionally, there is a suggestion to compute the time taken to move the distance of 78.6 m to help determine the final velocity. The conversation emphasizes the need to integrate the concepts of work, friction, and motion for a comprehensive understanding.
lostinthespiral
Messages
7
Reaction score
0
I am having real trouble understanding friction force. Work I understand. I just don't know how to put them together. Some help would be highly appreciated.

A 16.1 kg block is dragged over a rough, horizontal surface by a constant force of 118 N acting at an angle of 25 degrees above the horizontal. The block is displaced 78.6 m, and the coeficient of kinetic friction is 0.228. The acceleration of gravity is 9.8 m/s2.

a.) Find the work done by the 118 N force. Answer in units of J. - I've already found this to be 8405.82346 J

b.) Find the work done by the force of friction. Answer in units of J.

c.) If the block was originally at rest, determine its final speed. Answer in units of m/s2.
 
Last edited:
Physics news on Phys.org
Net work done on object = (horizontal component of 118 - frictional force) * distance

Net work done on object = change in kinetic energy (work-energy theorem)
 
lostinthespiral said:
I am having real trouble understanding friction force. Work I understand. I just don't know how to put them together. Some help would be highly appreciated.

A 16.1 kg block is dragged over a rough, horizontal surface by a constant force of 118 N acting at an angle of 25 degrees above the horizontal. The block is displaced 78.6 m, and the coeficient of kinetic friction is 0.228. The acceleration of gravity is 9.8 m/s2.

a.) Find the work done by the force of friction. Answer in units of J. - I've already found this to be 8405.82346 J

b.) Find the work done by the force of friction. Answer in units of J.

c.) If the block was originally at rest, determine its final speed. Answer in units of m/s2.


Please,review both the text (the first question and the second are identical),and the result to your first calculation.
For the third,compute the time in which the body moves along those 78,6 m and from there,u can find the velocity.
 
Alright. Fixed.
 

Thread 'Errors and significant figures'

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...
View full post »
Thread 'Calculation of Tensile Forces in Piston-Type Water-Lifting Devices at Elevated Locations'

Thread 'Calculation of Tensile Forces in Piston-Type Water-Lifting Devices at Elevated Locations'

Figure 1 Overall Structure Diagram Figure 2: Top view of the piston when it is cylindrical A circular opening is created at a height of 5 meters above the water surface. Inside this opening is a sleeve-type piston with a cross-sectional area of 1 square meter. The piston is pulled to the right at a constant speed. The pulling force is（Figure 2）： F = ρshg = 1000 × 1 × 5 × 10 = 50,000 N. Figure 3: Modifying the structure to incorporate a fixed internal piston When I modify the piston...
View full post »
Thread 'A cylinder connected to a hanging mass'

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...
View full post »

Similar threads

Finding the work done by a block
Replies
4
Views
3K
Why is the work done double its expected value? (conveyer belt)
2
Replies
58
Views
5K
Work Pulley Problem with constant speed
Replies
2
Views
986
Newton's law problem: Pushing 2 stacked blocks on a horizontal table
Replies
13
Views
3K
Finding Friction Force & Work with No Applied Force
Replies
8
Views
1K
My Mistake? Understanding Friction Force & Work Done on Snowy & Icy Surfaces
Replies
29
Views
2K
The Work of Friction: Explained in .32m
Replies
8
Views
2K
Friction problem of a block sandwiched between 2 surfaces
Replies
6
Views
1K
Work done by friction on a two-block system
Replies
7
Views
3K
Work-Energy Theorem and Friction
Replies
9
Views
3K

Hot Threads

Recent Insights

Back
Top