# 25 Physics Basic Questions With Answers

## 25 Physics Basic Questions With Answers

1-What is the SI unit of length?

The SI unit of length is the meter (m).

2-What is the formula to calculate velocity?

Velocity is calculated by dividing the change in displacement by the change in time. The formula is: Velocity = Displacement / Time.

3-What is Newton’s first law of motion?

Newton’s first law of motion, also known as the law of inertia, states that an object at rest will stay at rest, and an object in motion will stay in motion with a constant velocity unless acted upon by an external force.

4-What is the formula for calculating force?

Force is calculated by multiplying mass by acceleration. The formula is: Force = Mass × Acceleration.

5-What is the SI unit of force?

The SI unit of force is the newton (N).

6-What is the acceleration due to gravity on Earth?

The acceleration due to gravity on Earth is approximately 9.8 m/s².

7-What is Newton’s second law of motion?

Newton’s second law of motion states that the force acting on an object is equal to the mass of the object multiplied by its acceleration. The formula is: Force = Mass × Acceleration.

8-What is the formula for calculating work?

Work is calculated by multiplying force by displacement in the direction of the force. The formula is: Work = Force × Displacement × cos(θ), where θ is the angle between the force and the displacement vectors.

9-What is the SI unit of work and energy?

The SI unit of work and energy is the joule (J).

10-What is the principle of conservation of energy?

The principle of conservation of energy states that energy cannot be created or destroyed; it can only be transferred or transformed from one form to another.

11-What is the formula for calculating power?

Power is calculated by dividing work done by the time taken. The formula is: Power = Work / Time.

12-What is the SI unit of power?

The SI unit of power is the watt (W).

13-What is the law of universal gravitation?

The law of universal gravitation states that every particle in the universe attracts every other particle with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.

14-What is the formula for calculating electrical power?

Electrical power is calculated by multiplying voltage by current. The formula is: Power = Voltage × Current.

15-What is Ohm’s law?

Ohm’s law states that the current flowing through a conductor is directly proportional to the voltage across it and inversely proportional to its resistance. The formula is: Current = Voltage / Resistance.

16-What is the SI unit of electric current?

The SI unit of electric current is the ampere (A).

17-What is the difference between series and parallel circuits?

In a series circuit, the components are connected one after the other along a single path, and the current is the same through each component. In a parallel circuit, the components are connected across multiple paths, and the voltage is the same across each component.

18-What is the difference between speed and velocity?

Speed is a scalar quantity that measures how fast an object is moving, while velocity is a vector quantity that measures the speed and direction of an object’s motion.

19-What is the law of reflection?
The law of reflection states that the angle of incidence is equal to the angle of reflection, and the incident ray, the reflected ray, and the normal to the reflecting surface all lie in the same plane.

20-What is the difference between mass and weight?
Mass is a measure of the amount of matter in an object and is constant regardless of the location. Weight, on the other hand, is the force exerted on an object due to gravity and varies with the strength of the gravitational field.

21-What is the difference between potential energy and kinetic energy?
Potential energy is the energy possessed by an object due to its position or state, while kinetic energy is the energy possessed by an object due to its motion. Potential energy can be converted into kinetic energy and vice versa.

22-What is the formula for calculating momentum?
Momentum is calculated by multiplying the mass of an object by its velocity. The formula is: Momentum = Mass × Velocity.

23-What is the law of conservation of momentum?
The law of conservation of momentum states that the total momentum of a system of objects remains constant if no external forces act on the system. This means that the momentum before an event is equal to the momentum after the event.

24-What is the difference between a scalar and a vector quantity?
A scalar quantity is described by its magnitude (numerical value) only, such as time or temperature. A vector quantity has both magnitude and direction, such as displacement or velocity.

25-What is the difference between elastic and inelastic collisions?
In an elastic collision, both momentum and kinetic energy are conserved. In an inelastic collision, momentum is conserved, but kinetic energy is not conserved because some energy is transformed into other forms, such as heat or sound.