Ohhh. I see it now. For some reason I thought the problem simply said, "the generic boiling point of nitrogen is -196 C," and thus was wondering how we knew for sure it would get to -196 C.
If the initial temperature was NOT -196 C, then we would HAVE to know what the mass of nitrogen is to see...
Homework Statement
A 0.035 kg ice cube at its melting point is dropped into an insulated container of liquid nitrogen. How much nitrogen evaporates if it is at its boiling point of -196 C?
Nitrogen has heat of vaporization of 200000 J/kg
Ice's specific heat is 2100 J/kg*C
Homework Equations...
Hm..
The only substitution which I can make is this:
I am not sure how to get R in there.
It seems that the coefficient of fric. is not dependent on R.
Interesting, this follows:
http://www.feynmanlectures.info/solutions/roll_without_slipping_sol_1.pdf
On step 6, it says, "In order for the ball not to slip, the torque on the ball from friction can not be less than the total torque on the ball when it rolls"
(Note: I tweaked the problem from a slope to a flat ground for...
Homework Statement
I am solving a question that asks for, what's the minimum coefficient of friction required for a cylinder to roll without slipping? Where the cylinder has a force F acting on its center.
Homework Equations
And
The Attempt at a Solution
From the way I understand it, the...
Ohhh are you guys saying:
The potential energy at E is less than the potential energy at A?
(Without reference to the kinetic energy)
So thus the change in potential is negative, therefore the work done is positive?
Wait but this is how I understood it:
Point A had potential energy, and [K] kinetic energy
Point E has [U2] potential energy, which is less than .
If the system (cart and track) is energy conserving, then the decrease in must be transferred to an increase in [K]
Therefore, the kinetic energy at...
It is a weird question. But I guess the central point is that if we were to ignore the friction-less part, then the change in kinetic energy is negative, since the car would've had greater speed since it is at a lower height. So some kinetic energy was lost.
That is a very good point. We usually don't see coefficients of friction to be 1.0, so it probably was 0.1. I just wanted to make sure my understanding of work-energy relationship was correct. Thanks!
Homework Statement
If it can be assumed that the car has the same speed at points A and E, which of the following statements is true?
a. The net work done in this system is 0
b. The net work done in this system is positive
c. The net work done in this system is negative
d. The net work done in...
Homework Statement
Homework Equations
The block has potential energy U at the top of the ramp, and this is transferred to kinetic energy K at the bottom, which is then trasnfered to work done by friction, Wfr.
U = K Conservation of energy
K = Wfr Conservation of energy
g = 10 m/s2The Attempt...