Answer:
0.85 m/s²
Explanation:
Acceleration is change in velocity over change in time. In mathematically, it can be expressed as:

Our final velocity is given to be 17 m/s in 20 seconds. Initial velocity is at starting point which is 0 m/s in 0 second. Therefore:

Therefore, the acceleration of a horse from starting point to 17 m/s in 20 seconds is 0.85 m/s²
Answer:
Work done on an object is equal to
FDcos(angle).
So, naturally, if you lift a book from the floor on top of the table you do work on it since you are applying a force through a distance.
However, I often see the example of carrying a book through a horizontal distance is not work. The reasoning given is this: The force you apply is in the vertical distance, countering gravity and thus not in the direction of motion.
But surely you must be applying a force (and thus work) in the horizontal direction as the book would stop due to air friction if not for your fingers?
Is applying a force through a distance only work if causes an acceleration? That wouldn't make sense in my mind. If you are dragging a sled through snow, you are still doing work on it, since the force is in the direction of motion. This goes even if velocity is constant due to friction.
Explanation:
Answer:

Explanation:

The law of gravitation

Universal gravitational constant [S.I. units]

Mass of Earth [S.I. units]

Mass of a man in a spacecraft [S.I. units]

Earth radius [km]
Distance between man and the earth's surface
![h=261 \mathrm{~km} \quad[\mathrm{~km}]](https://tex.z-dn.net/?f=h%3D261%20%5Cmathrm%7B~km%7D%20%5Cquad%5B%5Cmathrm%7B~km%7D%5D)
ESULT 

Answer:
Answer is It was deduced from the rate at which it glimmers.
Refer below.
Explanation:
The X-ray source Cygnus X-1 has a mass of at least 11 solar masses and a diameter of only about one-quarter the diameter of the Earth. With such a small diameter it must be a compact object, and with such a large mass it can't be a white dwarf or a neutron star, so a black hole is the only possibility remaining. The diameter of Cygnus X-1 found:
It was deduced from the rate at which it glimmers.
This is a good time to review Newton's 3rd law of motion:
"For every action, there is an equal and opposite reaction."
Gravitational force always acts in pairs.
Whatever force the Earth attracts something with,
the thing attracts the Earth with exactly the same force.
If Earth
attracts a person with a gravitational force of <span><span>7.0 × 10² </span>newtons,
the person attracts Earth with a gravitational force of 7.0 × 10² newtons.
Your weight on Earth is the same as the Earth's weight on you !
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