Question

Please show the steps

1) Radio waves travel at the speed of light, 300,000 km/s. The wavelength of a radio wave received at 100 megahertz is            1) _______

A) 3.0 m.

B) 300 m.

C) 0.3 m.

D) 30 m.

E) none of these

22) Two charged particles repel each other with a force F. If the charge of one of the particles is doubled and the distance between them is also doubled, then the force will be    22) ______

A) F/4.

B) 2 F.

C) F/2.

D) F.

E) none of these

23) Two charged particles attract each other with a force F. If the charges of both particles are doubled, and the distance between them also doubled, then the force of attraction will be            23) ______

A) 2 F.

B) F/4.

C) F.

D) F/2.

E) none of these

Answer 1

(1)

Speed of light is

Frequency of the wave is

The wavelength of light

(22)

The electric force between two charge particles q₁ and q₂ separated by a distance r is

where k=9x10⁹Nm²/C².

Charge on one particle is doubled q₁'=2q₁

Distance between them is doubled r'=2r

The force between the two charge is

(23)

Charge on one particle is doubled q₁'=2q₁ , q₂'=2q₂

Distance between them is doubled r'=2r

The force between the two charge is