Question

The proto-galaxies in billions of years condensed to form galaxies due to the:

• A. electric forces
• B. magnetic forces
• C. electromagnetic forces
• D. gravitational forces

Answer 1

The correct option is D

gravitational forces

The explanation for the correct answer:

1. As we know according to the big bang theory 14 billion years ago our universe was concentrated in a very point size volume.
2. One day it suddenly exploded and its entire mass is thrown in all directions.
3. As a result islands of hydrogen and dust formed in the universe which are called protogalaxies.
4. These proto-galaxies condensed to form galaxies due to strong gravitational force.
5. A gravitational force is an attractive force that acts between two or more masses.

The explanation for the incorrect answer:

1. Electric force: The force of attraction or repulsion which act between two or more charges.
2. Magnetic force: The attractive or repulsive force which acts between magnets.
3. Electromagnetic force: It is the force experienced by a charged particle in the presence of magnetic field.

Hence the correct answer is option D.