Answer:
, 
Explanation:
The magnitude of the electromagnetic force between the electron and the proton in the nucleus is equal to the centripetal force:

where
k is the Coulomb constant
e is the magnitude of the charge of the electron
e is the magnitude of the charge of the proton in the nucleus
r is the distance between the electron and the nucleus
v is the speed of the electron
is the mass of the electron
Solving for v, we find

Inside an atom of hydrogen, the distance between the electron and the nucleus is approximately

while the electron mass is

and the charge is

Substituting into the formula, we find

Answer:
1. The number of turns on the secondary output is 18
2. The root mean square power delivered to the transformer is 48 Watts.
Explanation:
A transformer is an electronic device that can be used for increasing or decreasing the value of a given voltage. It consists of primary coils and secondary coil of a definte number of turns. When voltage flows in the primary coil, it induces voltage in the secondary coil. The two types are: step-up and step down transformers.
1. For a given transformer,
= 
where
is the value of the induced voltage in the secondary coil,
is he voltage in the primary coil, and
is the number of turns of the secondary coil,
is the number of turns in the primary coil.
From the question,
= 9.0 V,
= 120 V,
= 240,
= ?
So that,
= 
= 
= 18
The number of turns on the secondary output is 18.
2.
=
× 
= 0.4 × 120
= 48 W
The rms power delivered to the transformer is 48 Watts.
Answer:
The angular displacement is 
Explanation:
From the question we are told that
The initial angular speed is 
The angular acceleration is 
The time take is 
Generally the angular displacement is mathematically represented as

substituting values


Answer:
A ruler.
Explanation:
Just measure height, length and width and multiply each.