How Do You Calculate Kinetic Friction on an Incline?

[tmoney9876]

A 3.30 kg block starts from rest at the top of a 30.0° incline and slides 2.60 m down the incline in 1.50 s.
(a) Find the acceleration of the block.
4.9 m/s2
(b) Find the coefficient of kinetic friction between the block and the incline.

(c) Find the frictional force acting on the block.
N
(d) Find the speed of the block after it has slid a distance of 2.60 m.
Im very confused on even how to approach this.

 

[kamerling]

your answer for (a) would be true if there was no friction. you're supposed to find the
acceleration from the distance and the time.

The real acceleration will be the sum of all the other forces on the block, including the frictional force.

do (c) before (b)

 

[Moetasim]

I would suggest breaking down the problem into smaller, more manageable parts. First, we can use the given information to calculate the acceleration of the block. We can use the formula a = (vf - vi)/t, where vf is the final velocity, vi is the initial velocity (which is 0 since the block starts from rest), and t is the time. Plugging in the values, we get a = (2.60 m/1.50 s)/1.50 s = 4.9 m/s2.

Next, we can use this acceleration to calculate the coefficient of kinetic friction between the block and the incline. We can use the formula a = g(sinθ - μcosθ), where g is the acceleration due to gravity (9.8 m/s2), θ is the angle of the incline (30 degrees), and μ is the coefficient of kinetic friction. Plugging in the values, we get μ = (4.9 m/s2)/(9.8 m/s2)(sin30 - cos30) = 0.5.

To find the frictional force acting on the block, we can use the formula Ff = μmg, where m is the mass of the block (3.30 kg) and g is the acceleration due to gravity. Plugging in the values, we get Ff = (0.5)(3.30 kg)(9.8 m/s2) = 16.17 N.

Finally, to find the speed of the block after it has slid a distance of 2.60 m, we can use the formula vf2 = vi2 + 2ad, where vi is the initial velocity (0), a is the acceleration (4.9 m/s2), and d is the distance (2.60 m). Plugging in the values, we get vf2 = (0)2 + 2(4.9 m/s2)(2.60 m) = 25.48 m2/s2. Taking the square root, we get vf = 5.04 m/s.

I hope this helps you understand the problem better and how to approach it. Remember to always break down complex problems into smaller, more manageable parts and use the appropriate formulas and equations to solve them. Good luck with your homework!