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How to reduce friction?

How to reduce friction? Friction can be reduced in this way: By smoothing the surface. Using greasy materials. Using ball-bearing.

What is fundamental force? Gravitational force, Electromagnetic force, Weak nuclear forces and Strong nuclear force

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What is fundamental force? Those forces which are fundamental or independent meaning those forces which do not derive from other forces rather other forces are one type or another expression of them are fundamental forces. The four fundamental forces are: Gravitational force Electromagnetic force Weak nuclear forces and Strong nuclear force. Gravitational force The attraction force working between any two objects of the universe is the gravitational force. This attraction happens because of the mass. Among four fundamental forces, gravitational force is comparatively weaker. Electromagnetic force Two charged particles, because of their charge applies force on another which is called electromagnetic force. Weak nuclear force That short-ranged and weak force that works among the particles inside of a nuclear is weak nuclear force. Because of this force, instability occurs in the nucleus and Beta decay happens. Most  Strong nuclear force The strong force that works between two nucleons is

What is inertia of motion?

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  What is inertia of motion? The characteristics that a body in motion wants to keep its motion in uniform velocity, is called inertia of motion .

What is inertia of rest?

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What is inertia of rest? The characteristics that a stationary body wants to be stationary is called inertia of rest .

What do you mean by the law of conservation of momentum?

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What do you mean by the law of conservation of momentum? If no force other than action and reaction forces act on two or more objects, no change takes place in their sum momentums in the opposite direction. For example, the momentum of two cars are the same before and after a collision. If F 1  and F 2  stand for action and reaction forces, the law of conservation of momentum states that F 1  = F 2 . m 1 u 1 +m 2 u 2 =m 1 v 1 +m 2 v 2 Here, m 1  = mass of the first object m 2  = mass of the second object u 1  = initial velocity of the first object u 2  = initial velocity of the second object v 1  = final velocity of the first object v 2  = final velocity of the second object

You are standing on a weight measuring machine in a lift. If the cable of the lift tears, what is the weight that shows up on the machine?

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My weight will be zero. If the cable of lift tears, I, lift, and weight meter will fall down in the same acceleration. In this case, the applied force by me at the weight meter will be zero. That's why if the cable of lift tears, then my weight will be zero, i.e the weight meter will show zero reading.

When you try to get down from a moving train why do you fall in the forward direction?

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Why need to try to get down from a moving train we get the phone in the forward direction because of the inertia of motion. The full body of us remains in dynamic condition inside the moving train. But when we try to get down from the moving train, below the parts of our body become static. Fore inertia of moving parts of the upper body is dynamic. That's why when we try to get down from a moving train, we fall in the forward direction.

State the relation between the impulse of Force and the change of momentum.

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The relation between the impulse of Force and change of momentum: Change of momentum = force x time. The product of force and time is defined as the impulse of force. Therefore, the impulse of force = the change of momentum.

Explain how the concept of inertia is obtained from Newton's first law of motion.

From Newton's first law of motion, we observe that body cannot change its state by itself. If the body is at rest, it tends to remain at rest forever, and if it is in motion it tends to remain in motion with uniform speed forever. This property of a body is called inertia. Thus, from Newton's first law of motion, we get the concept of inertia.

Explain the impulse of Force.

The impulse of Force is the multiplication of applied force to a body and the application time. If a force F on a body is applied taking a time t then the impulse of Force is F x t. It is generally the change in momentum minus the initial momentum.

How the skydivers descend safely to the ground with the help of a parachute?

A parachute works by harnessing the air resistance. Air resistance is a type of frictional force that works against the force of gravity on Earth. As an open parachute has a large surface area, it helps provide enough air resistance. As a result, the skydivers falling speed is decreased mostly. So, the skydiver will then be able to descend slowly and safely.

If a stationary bus suddenly starts moving, the passengers lean backward - why?

If a stationary bus starts moving, the passengers inside the bus lean backward because the passengers wish to remain in their initial state of rest. This is known as inertia. As the bus starts to move, the passengers who are initially at rest will continue to remain at rest and So, they lean backward for an instance of time.

Explain how we walk.

In our daily life, you walk or run on the ground. When we walk on the ground, we accept a backward force on the ground by the leg behind obliquely. This is the action force. According to the third law, a reaction force is produced opposite to this. We are able to walk on the road due to this reaction force.

When a shot is fired from a gun, the gun pushes backward why?

When a shot is fired from a gun the gun is pushed backward at the time. In this case, the action and reaction force off the bullet and the gun exist at the same time.  According to Newton's second law of motion, the bullet and the gun equal and opposite momentum. As a result, the bullet moves forward with a particular momentum and the gun moves backward with a momentum of the same magnitude but opposite in direction. Due to this, the person will feel a backward thrust. The backward velocity of the gun will be smaller in compression to that of the bullet is the mass of the gun is large.

Write down the advantages of friction.

Though fiction has many advantages it is considered a necessary evil. We cannot do anything without the force of friction. If there was no friction, the motion of a body would not cases at all and continue perpetually. Due to friction, a nail is fixed in a wall. It became possible to construct buildings and houses because of friction. We can work as there is friction between our shoes and the ground. We can change the direction of motion of a car owing to fiction. Using a parachute it is possible to descend safely to the ground by Honey Singh the resistance. So, we can say that friction has so many advantages in our daily life.

Why does deceleration occur when a moving car is suddenly braked?

Velocity of a car decreases when it is suddenly braked, as a result deceleration occurs. In this case, the velocity is decreased by applying force opposite to the motion of the car. Deceleration is the decreasing rate of velocity with time. This is why deceleration occurs when a moving car is suddenly braked . 

What is inertia of motion?

When a body tends to remain in motion because of velocity then it is called inertia of motion. So, the characteristic of a body in motion wanting to keep its motion is called the inertia of motion . The inertia of the motion of a body depends on its momentum. When a moving bus is suddenly stopped, people bend forwards due to the inertia of motion . 

How to get the concept of inertia from Newton's first law?

 According to Newton's law, a stationary object will remain stationary and an object in uniform motion will continue its uniform motion. From Newton's first law, a force should be applied to change the stationary and motion state of a body. The characteristics of a body to keep its safe is called inertia.

Explain Pascal's law.

Pascal's law is a principle in fluid mechanics given by Balise Pascal that states that a pressure change at any point in a confined incompressible fluid is transmitted throughout the fluid such that the same change occurs everywhere. 

What is called pressre?

 Pressure is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. 

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