Total internal reflection. Although I'm not 100%
It's D. If it absorbed it would be turning to steam. I am taking honors chem in high school we are learning this.
Answer: 5 seconds
Explanation:
Given the following :
Inductance (L) = 40 henry
Resistance = 8 ohms
The circuit given above is a Resistor - Inductor (RL) circuit network. The time constant of an RL circuit is the ratio of the circuit Inductance (L) and Resistance (R). Time constant is measured in seconds.
THAT IS;
Time constant = L / R
THEREFORE ;
Time constant = 40 / 8
Time constant = 5 seconds
Explanation:
They probably put "rolls without slipping" in there to indicate that there is no loss in friction; or that the friction is constant throughout the movement of the disk. So it's more of a contingency part of the explanation of the problem.
(Remember how earlier on in Physics lessons, we see "ignore friction" written into problems; it just removes the "What about [ ]?" question for anyone who might ask.)
In this case, you can't ignore friction because the disk wouldn't roll without it.
As far as friction producing a torque... I would say that friction is a result of the torque in this case. And because the point of contact is, presumably, the ground, the friction is tangential to the disk. Meaning the friction is linear and has no angular component.
(You could probably argue that by Newton's 3rd Law there should be some opposing torque, but I think that's outside of the scope of this problem.)
Hopefully this helps clear up the misunderstanding for you.
