Answer:
Velocity of the electron at the centre of the ring, 
Explanation:
<u>Given:</u>
- Linear charge density of the ring=

- Radius of the ring R=0.2 m
- Distance of point from the centre of the ring=x=0.2 m
Total charge of the ring

Potential due the ring at a distance x from the centre of the rings is given by

The potential difference when the electron moves from x=0.2 m to the centre of the ring is given by

Let
be the change in potential Energy given by

Change in Potential Energy of the electron will be equal to the change in kinetic Energy of the electron

So the electron will be moving with 
= 27.777
Explanation:
A kilometer has 1,000 meters, and an hour has 3,600 seconds, so 100 kilometers per hour is: 100 x 1,000 / 3,600 = 27.777... m/s.
Answer:
Word for the first blank: gravity
Word for the second blank: matter
Explanation:
The only way debris from the impact with Earth can be held close to Earth is due to a force. The only force that could be acting from Earth is "the force of gravity".
The gravitational pull of this new object being formed, increases proportional to its mass as more and more "matter" accumulates. And the accretion process is now on its way.
1. Our solar system is the only place in the universe where gravity played a key part in the formation of planets.
2. Rocky planets are small, dense, and orbit relatively close to the sun, compared to the Jovian planets, which are large, less dense, and orbiting far from the sun.
3. _______