Coefficient of kinetic friction of force sensor

AI Thread Summary
The discussion focuses on calculating the coefficient of kinetic friction (mu k) for an 8.2 kg box on a horizontal surface, given that it starts moving with a force of 20.7 N and accelerates at 0.4 m/s². The user initially calculated the static friction coefficient (mu s) but struggled with mu k. They attempted to use the equations F=mg*mu k and ma=mg*mu k but found them unhelpful. A suggestion was made to set the net force equal to ma, which provided clarity on how to proceed. The conversation highlights the importance of understanding the relationship between force, mass, and acceleration in friction problems.
map7s
Messages
145
Reaction score
0

Homework Statement



A force sensor is used to measure a force applied to a 8.2 kg box on a hard, horizontal surface. It records that the box starts to move when the force is equal to 20.7 N. This force makes the box start to move with an acceleration of 0.4 m/s2. Find s and k respectively.


Homework Equations



f s=mu s*N
f k=mu k*N

The Attempt at a Solution



I found out what mu s was, but I am having trouble finding out mu k. I tried F=mg*mu k and ma=mg*mu k. Is there another way to go about solving this part of the problem?
 
Physics news on Phys.org
Set the net force equal to ma. (Two horizontal forces act on the box.)
 
oh...okay thanks! that helped!
 
Thread 'Collision of a bullet on a rod-string system: query'

Thread 'Collision of a bullet on a rod-string system: query'

In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
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

For the friction formula when to use Fn(normal force)×mu and when F×mu
Replies
17
Views
2K
Static Friction Between a Box and the Floor
Replies
11
Views
3K
Two blocks kept side by side and friction between them
Replies
9
Views
1K
Coefficient of Friction question for a cart going down a wooden ramp
Replies
18
Views
3K
How to find the coefficient of kinetic friction?
Replies
2
Views
2K
Constant frictional resistance & retardation
Replies
6
Views
1K
Block sliding on vertical track with friction (Solved problem)
Replies
4
Views
2K
Calculating acceleration from the coefficient of kinetic friction
Replies
48
Views
8K
Why Does the Friction Force Not Match in the Two Block Problem?
Replies
15
Views
3K
Yes! Calculating Friction Coefficient
Replies
1
Views
1K

Hot Threads

Recent Insights

Back
Top