Acceleration on a slant/coefficient of friction

Click For Summary
SUMMARY

The discussion centers on calculating the distance a block travels up an inclined plane with an initial speed of 6.00 m/s, an incline angle of 30 degrees, and a coefficient of kinetic friction of 0.330. The user initially misapplied the acceleration due to friction and gravity, leading to incorrect calculations. After reevaluating the forces involved, the correct acceleration was determined to be -2.80 m/s², which was then used to calculate the distance traveled up the incline. The final distance calculated was 6.42 m, which did not match the expected answer choices, indicating a need for further refinement in the approach.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Knowledge of kinematic equations, specifically delta_x = v_initial + 0.5a*t^2
  • Familiarity with the concept of friction, particularly the coefficient of kinetic friction
  • Basic trigonometry, especially in relation to inclined planes
NEXT STEPS
  • Review the derivation of the normal force on an incline and its impact on frictional force
  • Learn how to apply the work-energy principle in inclined plane problems
  • Study the effects of different coefficients of friction on motion up an incline
  • Practice solving similar problems involving inclined planes and friction to reinforce concepts
USEFUL FOR

Students studying physics, particularly those focusing on mechanics and inclined plane problems, as well as educators looking for examples of friction and motion analysis.

Crazdfanatic
Messages
2
Reaction score
0

Homework Statement



A block is given an initial speed of 6.00 m/s as it slides up an inclined plane that makes an angle of 30 degrees with the horizontal. If the coefficient of kinetic friction is .330, how far up the incline will the block go?

Homework Equations



I messed around with the equation delta_x = v_initial + .5a*t^2 , not sure how the coefficient of friction works

The Attempt at a Solution



I tried setting a = - 11.3 m/s/s by using trig because of the slant on the horizon, then using the above distance formula to find the maximum distance it traveled. I tried multiplying the coefficient of friction into the acceleration part of the equation, but to no avail. Please help me figure out what I'm doing wrong. Maybe an explanation of coefficient of friction is all I really need, I don't know.
 
Physics news on Phys.org
The coefficient of friction defines the relation between the normal force (exerted perpendicular to the contact surface) and the frictional force (which is parallel to the surface).

Ffrict = u x Fnormal

On a ramp, the normal force is no longer equal to simply mg, which is where the angles come in. Give it another try using these principles.
 
Okay, so I looked at it again, and this is what I got.

I found the new acceleration by g(u)cos(30) . I ended up getting a = -2.80 m/s/s.

From there, I plugged it into the distance formula above, leaving me with:

delta_x = t(6.00) + .5(-2.80)t^2

I took the derivative with respect to t to find the t that would give me the max distance.
I got this.

0 = 6.00 + (-2.80)t
t = 2.14 s

I plug that back into the above equation to get delta_x.

I ended up getting delta_x = 6.42 m, which is nowhere near any of the answer choices.

Am I even on the right track?
 

Similar threads

  • · Replies 8 ·
Replies
8
Views
959
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 16 ·
Replies
16
Views
6K
Replies
14
Views
3K
  • · Replies 11 ·
Replies
11
Views
3K
Replies
18
Views
3K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 33 ·
2
Replies
33
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 21 ·
Replies
21
Views
2K