Recent content by bartersnarter

I just had a thought... is friction the force which drives the car forward? The wheels spin in the negative x-direction (with respect to the ground) so the friction points to the positive x-direction. If that were the case it would make a lot of sense!

Homework Statement Homework Equations friction:[/B] f = μN incline angle: θ = arctan(1/10) summation of forces in y: N - mgcosθ = 0 summation of forces in x: -f - mgsinθ = ma (?) The Attempt at a Solution For this problem, I set the x-axis going up the incline and the y-axis normal to said...

Homework Statement Homework Equations vx = 70*cos(α) + 8.333 (30 km/h = 8.333 m/s) vy = 70*sin(α) vx*t = 350 vy*t = 60 -(1/2)*g*t^2 + vy*t + 2.5 = 60 The Attempt at a Solution This problem is conceptually very simple for me, but I can't solve it without using a solver like Wolfram Alpha...

Ah, I'm sorry, I meant y = 1/x, not y = ln(x).

Homework Statement A gas contained in a piston-cylinder assembly undergoes two processes, A and B, between the same end states, 1 and 2. State 1: P1 = 1 bar, V1 = 1 m3, U1 = 400 kJ State 2: P2 = 10 bar, V1 = 0.1 m3, U1 = 450 kJ Process A: Constant-volume process from state 1 to a pressure of 10...

Homework Statement Can anyone explained to me the factor of 2 in the equation for the intrinsic carrier concentration? Homework Equations ni is proportional to exp(-Eg/2kT) where ni is the intrinsic carrier concentration, Eg is the band gap energy, k is Boltzmann's constant, and T is...

Ahh, I see now! I had set up that sum of moments for part a and I neglected to alter it for part b. Thanks a bunch! After altering it I get F = uW/4. This makes much more sense!

The friction on the workpiece.

If the workpiece is moving to the left, the friction force should be towards the right, shouldn't it?

Homework Statement This is my problem in all its glory. Homework Equations f = uN The Attempt at a Solution For part a I simply did that tan(alpha) = f/N and therefore alpha = arctan(f/N). This simplifies to alpha = arctan(u). I believe this part is correct. The second part of this question...

Homework Statement Here's my problem. I only need help with the bottom part, but if you could explain the problem more vividly that would help too. Homework Equations A = S-1BS (?) There aren't really any relevant equations. This part of linear algebra is getting really abstract, at least I...

The tension is greater at the mass. I believe tension increases opposite to the direction of acceleration for a massive rope. If the tension is negative, I think I put the sign there to show that it was in the opposite direction. I meant to write T2 - T3 = 0. I believe the rest of the equations...

Homework Statement Here is my problem: Homework Equations Here is my work thus far and all the equations I've included. The Attempt at a Solution I'm not completely sure if my work is correct. I keep writing and erasing the tension equations because I can't decide which are right. Can...