No, it is not necessary to memorize the names of all scientists and their principles for NEET UG 2019. However, it is important to have a basic understanding of the concepts and principles they have discovered in order to excel in the physics section of the exam.

Physics and Fundamental Forces - Physical World is a very important topic for NEET UG 2019. This topic covers the basic principles of physics and fundamental forces that govern our universe. Here are some of the key points that you need to know about this topic:

Key Concepts:
- Physics is the study of matter and energy and their interaction with each other.
- The fundamental forces of nature are gravitational, electromagnetic, weak nuclear, and strong nuclear forces.
- These forces govern the behavior of all matter and energy in the universe.
- The laws of physics are universal and can be applied to everything from the smallest subatomic particles to the largest galaxies.

Gravitational Force:
- Gravitational force is the force of attraction between any two objects with mass.
- This force is responsible for keeping planets in orbit around the sun and holding galaxies together.
- The strength of the gravitational force depends on the masses of the objects and the distance between them.

Electromagnetic Force:
- Electromagnetic force is the force that causes electrically charged particles to attract or repel each other.
- This force is responsible for all electrical and magnetic phenomena, such as the behavior of magnets and the flow of electricity.
- The strength of the electromagnetic force depends on the charges of the particles and the distance between them.

Weak Nuclear Force:
- Weak nuclear force is responsible for radioactive decay and the conversion of one type of particle into another.
- This force is much weaker than the other fundamental forces and only operates over very short distances.

Strong Nuclear Force:
- Strong nuclear force is responsible for holding the nucleus of an atom together.
- This force is the strongest of all the fundamental forces and only operates over very short distances.

Conclusion:
In conclusion, understanding the principles of physics and fundamental forces is very important for NEET UG 2019. While it is not necessary to memorize the names of all scientists, it is important to have a basic understanding of the concepts they have discovered. By mastering this topic, you will be able to answer questions related to physics and fundamental forces with ease.

Yes I m not sure but may be some questions can appear... Better u prepare it