Frequency represents the number of complete oscillations in one second. it is measured in Hertz (Hz). Electromagnetic waves are waves which do not require a material media for transmission. They travel with a speed of light.
The speed (m/s) of a wave is given by frequency (Hz) × Wavelength (m)
Speed is 300,000 km/sec or 300,000,000 m/s and the wavelength is 300,000 km or 300,000,000 m.
Frequency = speed÷ wavelength
= 300000000 ÷ 300000000 = 1
Therefore, the frequency of the wave is 1Hz
<span>rocky surface
(outer plants are made of gas)</span>
We need to charge a metal sphere positively without touching it. This can be achieved using electrostatic induction.
Answer:
- 2.425 x 10^5 J
Explanation:
The gravitational potential energy between earth and the bock is given by

Where, G is the universal gravitational constant = 6.67 x 10^-11 Nm^2/kg^2
M is the mass of earth = 5.8 x 10^24 kg
m is the mass of block = 4 kg
r be the radius of earth = 6380 km = 6380 x 10^3 m
by substituting the values in the above expression, we get

U = - 2.425 x 10^5 J