Accelerating Definition and 669 Threads

This problem is keeping me up all night, I did what I thought was right to figure out the force needed but the answer sheet tells me that my solution is wrong, spend 4 hours trying to figure out what I did wrong can't come up with anything: A 280kg box slides 4.3m down a 30 degree incline and...

I am having difficulties finding an acceptable rationale for my solution to Problem 41 of Chapter 5 from Physics for Scientists and Engineers, 4th edition, by Paul A. Tipler: Lou has set up a kiddie ride at the Winter Ice Fair. He builds a right-angle triangular wedge, which he intends to...

I am having difficulty solving Problem 105 of Chapter 4 from Physics for Scientists and Engineers, 4th edition by Paul A. Tipler: The pulley in an Atwood's machine is given an upward acceleration \overrightarrow{a}. Find the acceleration of each mass and the tension in the string that...

The driver of a pink Cadillac traveling at a constant 60 mi/h is being chased by the law. The police car is 20 m behind the perpetrator when it too reaches 60 mi/h, and at that moment the officer floors the gas pedal. If her car roars up to the rear of the Caddilac 2.0 s later, what was her...

Here is a discussion Question : Overlooking the planet's own motion, why is it likely that everything moving for any appreciable distance on the surface of the Earth is accelerating? Pleas help me with this question. I think it's talking about acceleration due to changing the velocity...

Seen in another thread: Does this implies that a spaceship, inside a black hole, accelerating in the direction OPPOSITE to the singularity would actually accelerate TOWARDS the singularity? Or does it simply mean that no matter how fast a speed he reaches through his acceleration, he would...

if, say, an electron is stationary on Earth (ignore the probability or possibility of this for now). it, of course, is not emitting any EM radiation. However, an observer in space (stationary with reference to the sun) is looking at the electron. relative to them, the electron is accelerating...

As the universe expands and disperses, there is less of a gravitational well for photons to climb out of before they reach us. Photons from the early universe must climb out of the gravity well of a more densely populated universe than photons emitted from sources today. Therefore early photons...

A car, initially still, accelerates up to a maximum speed of v, and then slows down to a stop again. The plot of the velocity over the time (t seconds from start to stop) is a semicircle. (i'm sorry i cannot post the diagram, but try to imagine it, it is a simple semicircle where the topmost...

What if... Gravity is the consecuence of mass deforming space-time. But why mass deforms space-time? What if gravity is the consecuence of mass inertia in an accelerated universe. I can imagine a universe expanding at an accelerated speed that is being deformed by the inertia of the objects...

Two frame of reference A and A'. A' starts accelerating with respect to A. The distance of separation of the two frame of reference is s = 1/2 at^2 x' = x - s = x - 1/2 at^2 Differentiating twice with respect to time we get d^2x'/dt^2 = d^2x/dt^2 - a d^2'x/dt^2 + a =...

I read in Brian Greene’s book that a founding principle of Einstein’s SR/GR theory is based on… the laws of science should remain the same for all freely moving (non-accelerating) observers. I have read that a few times before but worded a little differently. My question is, does this mean...

An electron is accelerated through 1800V from rest and then enters a uniform 2.90T magnetic field. What are the maxium and minium values of the magnetic force this charge can experience? Ok someone help me out here...not sure of the equation. How do the formulas for a magnetic force differ...

1. Let clock A and clock B be of identical construction, and let them both not be subjected to any force. Let them be at rest with respect to each other. Thus, the relative velocity v is equal to zero. Therefore, using Newtonian mechanics or SR, the clocks tick at the same rate. For the...

Allright, this isn't exactly a K-12 question, but I am trying to learn something on my own, since I don't think I learn enough at my school. Anyway, I am working with Basic Physics secound edition, and I really need some place to ask for help since I am stuck. I have come to a place, where I...

I have been stuck on this problem for so long... It's seriously driving me insane. The problem: An incline plane that makes an angle of 28 degrees to the horizontal is mounted on wheels. A small block of mass m=0.9kg rests on the plane, held there by a coefficient of static friction...

Here is the problem from one of my online homework site. :-( An object starts at time t = 0 with a velocity of v0 = +4 m/s and undergoes a constant acceleration of a = -17 m/s2. There's five small parts to this problem but I got 4/5 done. I'll post them anyway to give you guys a clearer...

Someone is shooting faster than light particles at you and you accelerate toward the shooter. Do the tachyons speed up, slow down or remain the same speed?

As far as I am aware scientists agree that the universe is flat, open or closed. However, if galaxies get further away from each other the gravitational attraction between them would decrease as the universe expands. Why is the universe speeding up not a real possibility?