Answer:
Velocity of the electron = v = 1.2\times 10^8\ m/s.
Explanation:
Given,
- Mass of the electron =

- Charge on the electron =

- Charge density of the ring =

- Radius of the ring = R = 0.70 m
- Distance between the electron ant the center or the ring = x = 0.5 m
Now total charge on the ring = 
Potential energy due to the charged ring to the point on the x-axis is

Let v be the velocity of the electron at the center of the ring.
Total kinetic energy of the electron = 
Now, From the conservation of energy,
the total potential energy of the electron at initially is converted to the total kinetic energy of the electron at the center of the ring,

Hence the velocity of the electron on the center of the charged ring is 
Answer:
Half
Explanation:
Given that:
- radial distance of satellite from the earth,

Now, if the satellite is moved to a distance 
<u>We have the mathematical expression for the potential energy fue to gravitational field as:</u>
...................(1)
where:

M = mass of earth
m = mass of satellite
R = radial distance of satellite
<u>Now from eq. (1) initially we have:</u>

<u>after the satellite is moved, we have:</u>



which is half of the initial condition.
Air resistance, also called drag, acts upon a falling body by slowing the body down to thr point where it stops accelerating, and it falls at a constant speed, known as the terminal volocity of a falling object. Air resistance depends on the cross sectional area of the object, which is why the effect of air resistance on a large flat surfaced object is much greater than on a small, streamlined object.
He arranged his periodic table by each elements atomic mass