When things are at rest (not moving relative to the frame of reference) and cold absolute zero.
Any definition of motion has to be relative to a frame of reference. My book is at rest on the table but the Earth is spinning & orbiting the sun. If we take the room or the Earth as a frame of reference my glass is at rest. If we take the sun as our frame of reference my book is moving very fast.
Yes. Consider both the objects to be moving with the same velocity in the same direction. Then, the velocity of one of the objects with respect to the other is zero and vice versa, i.e., relative velocity is zero. If the relative velocity is zero,i.e., one object appears to have zero velocity (no velocity) with respect to the other, then they are considered to be at rest with respect to each other.
An object that is moving has momentum, or kinetic energy.
If an object is at rest relative to you, then itsmomentum is zero as far as you're concerned.
Everything else in the car that is not itself rotating etc. is at rest relative to the passenger -- the seats, car body, dashboard, windows, etc, "At rest" is in this case just another way to say "moving at the same velocity."
The train.
The front seat of the car.
the front seat of the car I think.....
Being at rest is a relative term. Relative to earth we are at rest when we are sitting down. However, you are moving because the earth is moving its orbit around the sun.
Being at rest is a relative term. Relative to earth we are at rest when we are sitting down. However, you are moving because the earth is moving its orbit around the sun.
Being at rest is a relative term. Relative to earth we are at rest when we are sitting down. However, you are moving because the earth is moving its orbit around the sun.
When an object is at rest, it is only at rest compaired to the observer. Consider that if you are in a moving vehicle then your passenger is at rest from your point of view, but to an observer, outside the vehicle the passenger and you are both in motion. Similarly to you inside the vehicle the observer outside is moving . as the earth itself is in motion, as well as the sun and in fact the whole galaxy, their is no way to absolutely define an at rest state, so all motion is measured relative to the observer, who is assumed to be at rest compaired to the observation.
As a passenger in a car !
Actually sitting on the earth we feel as if we are at rest. But relative to the pole star we are moving along a circular path. Also relative to the sun we are moving along an elliptical path around the sun. So actually speaking we are not at rest. In the same nothing is stationary. Everything is in motion. Rest means only a relative term.
All motion is relative. The question "is this object moving?" is in fact meaningless unless we specify "moving relative to what other object". Similarly, there is no such thing as "absolute rest": it's just as true to say that the road is moving at 50 km/h relative to your car as it is to say that your car is moving at 50 km/h relative to the road.
Yes and no. All motion is relative. When you say you are moving you mean in relation to something else. If are on the train and you choose something that moving alongside you at the same speed (another train for instance) then you are not moving relative to that, however you are moving in relation to the countryside. Both trains are moving in relation to a cow in the field.