Hey there!
Your correct answer would be (<span>
Every mass exerts a gravitational force on every other mass.) It really doesn't matter the size in mass what so ever, gravity is stronger than mass, mass in nothing compared to mass. Therefor, gravity exert's mass on any object with any size of mass.
Your correct answer would be
. . .
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<span>
Hope this helps.
~Jurgen</span>
Answer:
Average velocity

Average speed,

Explanation:
(a)Average velocity
We have to find the average velocity. We know that velocity is defined as the rate of change of displacement with respect to time.
To find the average velocity we have to find the total displacement.
since displacement along east direction is 50m
and displacement along west=40m
so total displacement,

total time,

therefore, average velocity

(b)Average Speed:
Average speed is defined as the ratio of total distance to the total time
it means
Average speed= total distance/total time
here total distance,

and total time,

therefore,
Average speed,

Answer:
D
Explanation:
1.) The reaction is at dynamic equilibrium.
A: Nitrogen and hydrogen combine at the same rate that ammonia breaks down.
2.) Which statement about the reaction is necessarily correct?
A: Both calcium carbonate and sodium carbonate are being produced.
3.) Both calcium carbonate and sodium carbonate are being produced.
A: The reaction is reversible.
4.) What is the fastest motion that can be measured in any frame of reference?
A: 300,000 km/s
5.) Two people are on a train that is moving at 10 m/s north. They are walking 1 m/s south relative to the train. Relative to the ground, their motion is 9 m/s north.
Why are we able to use these motions to describe the motion relative to the ground?
A: The people are moving much slower than the speed of light so the ground acts as a frame of reference.
Answer:
There would be tremendous earthquakes and tsunamis, followed by massive volcanism around the impact zone. The ozone layer would be destroyed. The oceans would turn acidic. The Sun would be blotted out, probably for decades.
Explanation:
Hope this helps!
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.