Homework Statement
Determine the voltage drop across R1
R1 = 770 , R2 = 630 , and R3 = 470 .
The equivalent resistance is 816Ω
Homework Equations
V = IRThe Attempt at a Solution
1.) I find the total current of the circuit:
V = IR -> I = V/R
I = 12v/816Ω = 0.015A
2.) I then find the...
Ah... so if I were to sum the forces:
0 - (u*30*9.8) = 60
u = .204
It works!
If you don't mind me asking another question, can you explain you reasoning for: v2 = vi2 + 2a(x - xi)
16 = 4 + 2*a*3
Why don't you use 2m/s for the final velocity?
Thanks!
I don't understand how I'm using the same force twice. I take the force pushing the object forward and subtract the force of friction pushing in the other direction. When summing forces I thought it is necessary to set their sum equal to ma. Am I missing something fundamental?
Thanks!
Ok, I see why it is 180J, thanks! Here is my revamped work:
W = fd
180J = f * 3m
f = 60N
60N - (u * (30*9.8)) = (2/3) * 30
u = -.14
This is not a choice, though:
a.) 0.07
b.) 0.12
c.) 0.20
d.) 0.27
e.) 0.60
When I use W = Fd and F = umg , I get .204 (an answer choice).
So why doesn't this...
Thank you for your response.
When I sum up the forces, I set them equal to ma. I need acceleration so I can solve for the coefficient of friction.
Can you please explain how you found work to be 180J .
Thanks!
Homework Statement
A 30kg sled is sliding on a frictionless sheet of ice at a velocity of 4m/s. The sled encounters a rough patch of ice and begins to slow down. After traveling on the rough patch of ice for 3m, the sled's velocity is 2m/s. Determine the coefficient of friction between the...
Yes, but isn't mass 1 accelerating downwards as well. It also is being affected by gravity. Why then is it equal to positive ma and not negative ma. I expect it to be negative, but that is not the case. Am I missing something obvious?
Thanks!
I see, thanks. But why is T - m2g = to a negative m2a ?
What is the reasoning behind m2a being negative. If when dealing with the first mass ma is positive; what makes the difference here?
Why is one Tension Negative and the Other Positive -- Atwood Machines
Hello,
Please consider the following:
I am trying to understand how to solve for acceleration when dealing with Atwood machines. I keep getting hung up on one part: the direction of tension. In the image above, why is...
Hello,
I recently was thinking about an idea for a perpetual battery. I have an extremely limited amount of Physics knowledge (just a Conceptual Physics [Algebraic Physics] class) as I am still in high school. Does anyone know if this would work:
1. Have a tube
2. Wrap the tube in copper...