Correct Answer - Option 2 : electrical forces
CONCEPT:
Gravitational force |
Electric force |
Magnetic force |
Nuclear force |
Gravitational force is the force of attraction between two masses. It is one of the four fundamental forces of nature. |
When two charges are kept close to each other a force acts between them. The force between the two charges is called an electric force.
|
When two magnetic poles are kept close to each other a force acts between them. The force between the two magnetic poles is called magnetic force.
|
The nuclear force is the force that binds the protons and neutrons in a nucleus together. The range of a nuclear force is 10-15 m. |
It is the weakest of the four. It is always of attraction nature.
|
Like charges repel each other while the unlike charges attract each other. |
Like poles repel each other while the unlike poles attract each other.
|
This force can exist between protons and protons, neutrons and protons or neutrons. |
EXPLANATION:
- The electron and the proton are 10-10 m apart.
- We know that the range of a nuclear force is 10-15 m and the electron and the proton are 10-10 m apart so there will be no nuclear force.
- For magnetic force, the charges must be in motion so there will be no magnetic force between the charges.
- By coulombs law, the electric force between the electron and the proton is given as,
\(⇒ F_{e}=\frac{kee}{r^{2}}\)
Where e = 1.6×10-19 C and k = 9 × 109 Nm2/C2 (For vacuum)
\(⇒ F_{e}=\frac{9×10^9×(1.6×10^{-19})^2}{10^{{-20}}}\)
⇒ Fe = 23.04×10-9 N -----(1)
- The gravitational force between the electron and the proton is given as,
\(⇒ F_{g}=\frac{Gm_em_p}{r^{2}}\)
Where G = 6.67×10-11 Nm2/kg2, me = 9.1×10-31 kg, mp = 1.67×10-27 kg and r = 10-10m
\(⇒ F_{g}=\frac{6.67×10^{-11}×9.1×10^{-31}×1.67×10^{-27}}{10^{-20}}\)
⇒ Fg = 10.14×10-49 N -----(2)
- By equation 1 and equation 2 it is clear that the electric force is much much higher than the gravitational force. So the net effect between the electron and the proton will be due to the electric force.
- So their relative motion is chiefly determined by an electrical force.
- Hence, option 2 is correct.