Thanks for helping :D
However, I still don't get it. What exactly is M_1, M_2 and V_1 and V_2 in this case, and how do the initial equations arrive at the conclusion through the arrows? Could you please elaborate? I kind of see how the math works, but I don't know how it arrives at the...
Homework Statement
A large wedge rests on a horizontal frictionless surface. A block starts from rest and slides down the inclined surface of the wedge, which is rough. During the motion of the block, the center of mass of the block and wedge.
a. does not move.
b. moves horizontally with...
Homework Statement
A 1500kW heat engine operates at 25% efficiency. The heat energy expelled at the low temperature is absorbed by a stream of water that enters the cooling coils at 20 degrees C. If 60L flows across the coils per second, determine the increase in temperature of the water...
No, you were right. Let me rephrase that.
Let m1 be the mass on the left, and m2 the mass on the right. Let T1 be the tension holding up m1 and T2 be the tension holding up m2. So would T1 also be the force that applies the counterclockwise torque, and T2 the clockwise torque?
I always...
Thanks for answering.
Well, the equation you gave (T1-T2 = Ia/r^2) is the same as the one I got, just multiplied by -1 on both sides (T2-T1 = -Ia/r^2). In your case, you are designating T2 as negative and thus counterclockwise. Shouldn't the acceleration still be negative then?
As for the...
Homework Statement
A pulley has a moment of inertia of 5.0 kg*m^2 and a radius of 0.5m. The cord supporting the masses m_1 and m_2 does not slip, and the axle is frictionless. Find the acceleration of each mass when m_1 = 2.0 kg and m_2 = 5.0 kg.
Homework Equations
F=ma, Fr=I(alpha)...
I was doing the IPhO F=ma test from 2008 and couldn't get these two questions.
Question 1
Homework Statement
A car has an engine which delivers a constant power. It accelerates from rest at time t = 0, and at t = t_0 its acceleration is a_0. What is its acceleration at t =2t_0? Ignore energy...
Hey guys,
Do any of you happen to know how to derive the formula for General gravitational potential energy (not the mgh one) without using calculus? Thanks.
Just in case you guys want to know, I'm trying to derive the equation for this: http://xkcd.com/681_large/. I've got most of it, but I...
I was reading xkcd and wondering if spinning in a counterclockwise way (on the northern hemisphere) would actually steal some of earth's angular momentum and slow it down a bit. Is it possible or does this violate conservation of momentum?
actually, you're also wrong about the energy not escaping. energy is slowly leaked out of black holes, and the black holes themselves destingerate after immensly long period of time.
An, the light affected by gravity is explained in the local frame/closed rocket acceleration thought expiriment...
well yes, gravity waves do travel at the speed of C. (don't get the waves confused with a gravitational feild itself tho O_o) i dunno about the rest. [:
oh yeah forgot 2 add this too,
well, i'm not sure if you really can say that the light uses the spacetime as a medium because when ther's no...
that's true, the black holes do evaporate over immensly huge periods of time. the matter that the balck hole sucks in is eventually leaked out, even though it's not in the form of the atoms, particles, e.t.c that it came in in.
hmmm
well, no the gas wouldn't get extra pressure. because it's not the box that contracts, it's space itself. THe gas is in the box so both would undergo a lorentz contraction because both of them are in that local inertial frame.
actually, you can get as close as possible to the speed of light, but you cannot reach the speed of light in a vaccuum, because it would take an infinite impulse to reach the speed of light.
there might be a teensy weensy little problem. because of the low pressure on mars, any water would immediately boil and evaporate, even if the temperature is below zero. if we do grow algea, it would have to be in a pressurized environment or else if it was exposed to outside it would...
If black holes stretch the space-time fabric because of their mass existing in singularity, if you were near a black hole, wouldn't there be a time-stretch?
isn't time always the same to the observer? Meaning that you'll never notice time "stopping" or slowing down, as long as you're the one who's in that particular time frame.
You'rre correct, the angular momentum and the charge are retained by the balck hole. THe mass is also retained, to be slowly leaked out in another form later, not in the costituent atoms that enters, so in effect, black holes are just universal recycle bins. =)