What Is Motion In Physics

Force And Motion Relation

Force and motion are deeply related in nature. We can say that force is the cause of motion. Suppose something is moving, we can say that some force must be acting on it or some force must have acted on it which produced this motion. If a person is walking, and hence in motion, there must be some force acting on it which is making him move. What is this force? This force is the muscular force of his body.

Before we delve into the relationship between force and motion, let us first take a quick look into what is meant by force. Simply put, force is either a push or a pull. Force is defined as any interaction that, when unopposed, will change the motion of an object. By the definition itself, it is clear that force affects the state of motion of an object.

But what exactly is does state of motion mean? In physics, motion is defined as the change in position with respect to time. In simpler words, motion refers to the movement of a body. Typically, motion can either be described as

• Change in speed, or
• Change in direction.

Sir Isaac Newton was the first person to discover the relation between motion and force. From his studies in force and laws of motion we can come to the following three conclusions:

• Force can accelerate the body
• Force decelerate the body
• Force can change the direction of the moving body

Force Can Cause A Body To Accelerate

When force is applied to a body in rest, it starts to move, provided that there is no greater force opposing it. When you throw the ball towards the batsman while playing cricket, the ball starts to move forward from its initial position of rest in your hands.

When something begins to move from a state of rest, it accelerates. Acceleration can be described as a positive change in velocity over a period of time.

Similarly, if force is applied in the same direction of movement of a moving object, it accelerates. For example, if you rotate the pedal of a bicycle, it will go faster.

How To Identify An Object/body In Motion

Its pretty clear from the above text that we can determine any movement in the object by comparing its new position from the original position. Any change in the position of the object, with respect to time, is considered to be a motion. We find several things that keep on moving like Earth that appears to be still, is always in motion in an actual sense. Everything on Earth that appears still is actually in motion as the Earth itself is in motion .

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What Is Motion And Types Of Motion

Motion is the change with time of the position or orientation of a body. Everything in this universe is in a state of continuous movement, for example, the motion of animals and humans. Besides this, the basic particle of a matter a.k.a the atom is also in the state of continuous motion too. By this, we mean that every single physical procedure in this universe possesses some type of motion, and the motion either be slow or fast, but it is always present.

You can find objects moving everywhere. The motion of animals and humans are everyday examples of motion. The basic particle of a matter, i.e., the atom is in the state of continuous motion too. Every single physical procedure in this universe is made up of some type of motion. It can be either slow or fast, but the motion is present. However, if a man is snoring, do we say he is in motion or the chirping birds resting on the tree are in motion? If not, then how do we define the movement in an object or a living?

What Are Some Daily Life Examples Of Newtons 1st 2nd And 3rd Laws Of Motion

• The motion of a ball falling through the atmosphere or a model rocket being launched up into the atmosphere are both excellent examples of Newtons 1st law.
• Riding a bicycle is an excellent example of Newtons 2nd law. In this example, the bicycle is the mass. The leg muscles pushing on the pedals of the bicycle is the force.
• You hit a wall with a certain amount of force, and the wall returns that same amount of force. This is an example of Newtons 3rd law.

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Types Of Motion In Physics

The motion of an object depends on the type of force acting on the body. Examples of different kinds of motion are given below.

• Translational It is the type, where an object moves along a path in any of the three dimensions.
• Rotational It is the type, where an object moves along a circular path about a fixed axis.
• Linear It is a type of translational motion where the body moves in a single direction along a single dimension.
• Periodic It is the type of motion that repeats itself after certain intervals of time
• Simple Harmonic It is the type of motion like that of a simple pendulum where a restoring force acts in the direction opposite to the direction of motion of the object. This restoring force is proportional to the displacement of the object from the mean position.
• Projectile It is the type of motion which has a horizontal displacement as well as vertical displacement.
• Oscillatory It is the type of motion which is repetitive in nature within a time frame. If it is mechanical it is called vibration.

The Relation Between Force And Motion

Force and motion deeply connect in nature. In other words, force is the cause of motion. If something is moving, we will say that some force is acting on it or some force must have acted on it which is producing this motion.

If a woman is walking, and hence in motion, there must be some force acting on her which is making her move. So you ask, what is this force? It is the muscular force of her body. In simpler terms, force is neither a push nor a pull.

It is any interaction that, when unopposed, will change the motion of an object. By the definition itself, it becomes clear that force affects the state of motion of an object. Moreover, motion is the change in position with respect to time.

Naturally, we can describe motion as a change in speed, or change in direction. The first person to discover the relation between both was Sir Isaac Newton. He concluded that force can accelerate the body, decelerate the body and it can change the direction of the moving body.

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What Is Motion In Physics

In physics, motion is that phenomenon during which an object changes its position over time. Motion is calculated or described in terms of distance, velocity, displacement, acceleration, speed, and time. The motion of a body is observed by attaching a frame of regard to an observer and measuring the change in position of the body relative thereto frame with the change in time.

When an object doesnt change its position relative to a given frame of reference, the thing is said to be at rest, motionless, stationary, or time-invariant position with regard to its surroundings. Motion is present everywhere, in various physical systems: like matter particles, matter fields, bodies, radiation, radiation fields, radiation particles, curvature and space-time.

What Is Circular Motion

Circular motion is described as a movement of an object while rotating along a circular path. Circular motion can be either uniform or non-uniform. During uniform circular motion the angular rate of rotation and speed will be constant while during non-uniform motion the rate of rotation keeps changing.

Some of the most common examples of circular motion include man-made satellite that revolves around the earth, a rotating ceiling fan, a moving cars wheel, the blades in a windmill, and gears in gas turbines.

A particle is said to execute circular motion when it moves along the circumference of a circular path. An important aspect of circular motion is that the direction of motion is changing continuously unlike in the case of linear motion. Hence circular motion can also be described in terms of angular variables.

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Motion Along A Straight Line

• Motion along a straight line is the simplest form of motion.

• Magnitude is the numerical value of a physical quantity.

• The shortest distance, which is measured from the initial to the final position of an object is called as the displacement.

• The magnitude of the displacement for a path of motion may be zero but the corresponding distance covered cannot be zero.

• If an object travels equal distances in equal intervals of time, it is said to be in uniform motion.

• If an object travels unequal distances in equal intervals of time, it is said to be in non-uniform motion.

Force And Motion Formula

From Newtons second law of motion, the relationship between Force and motion can be mathematically expressed as:

• Force is defined as the product of mass m and acceleration a and is given as:

• Motion is explained using laws of motion and is defined as the particles behaviour when in motion and is given as:

Where,

• s is the position of the particle
• s0 is the initial position of the particle
• v0 is the initial velocity of the particle
• a is the acceleration
• t is the time

To wrap up, force and motion are two heavily connected entities. Force can result in the acceleration, deceleration, change in direction or total cessation of motion.

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Newtons First Law Of Motion

Newtons first law of motion implies that things cannot start, stop, or change direction all by themselves, and it requires some force from the outside to cause such a change. This property of massive bodies to resist changes in their state of motion is called inertia. The first law of motion is also known as the law of inertia.

Newtons 1st law states that a body at rest or uniform motion will continue to be at rest or uniform motion until and unless a net external force acts on it.

The crucial point here is that if there is no net force resulting from unbalanced forces acting on an object, the object will maintain a constant velocity. If that velocity is zero, then the object remains at rest. And if an additional external force is applied, the velocity will change because of the force.

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What Is A Motion

Kinematics is a branch of physics that deals with the objects in motion. It encompasses the study of the motion of small masses like points, objects, as well as a cluster of objects without taking into account the factors causing its motion, for instance, the forces applied over it. Kinematics can also be termed as the Geometry of Motion. Kinematics involves the evaluation of mathematical expressions, in order to study and analyze different aspects of motion such as velocity, acceleration, displacement, time, and trajectory.

The branch of physics concerned with the motion of material objects in consideration of the physical factors affecting them, that is force, mass, momentum, energy is known as the Dynamics.

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What Are The Laws Of Projectile Motion

Projectile motion is the motion of an object projected into the air,which moves under the influence of gravity.

Ballistics The Study Of Projectile Motion:

The science of mechanics that deals with the flight, behaviour, and effects of projectiles are called ballistics. The word ballistics comes from the word ballista, which was a siege machine used for war during the late 18th century. Ballista was a weapon that is used to hurl boulders or spears against the enemy troops or walls. The boulder or spears used against the enemy were launched by the ballista, after which it would travel in a parabolic path and land among the enemy. The operators of the ballista have to be concerned about the angle to launch the projectile and the path they had to travel to gauge the landing position of the ballista. This is the reason the study of projectile motion is called ballistics. The path travelled by the projectile after it is launched is called the ballistic trajectory. The study of ballistics is important in modern warfare since it involves calculating the trajectories of modern warfare equipment like bullets, unguided bombs, rockets, and such other equipment. It also involves the designing of projectiles to attain desired acceleration and performance.

The weapon with the highest potential for destruction is named the ballistic missile since it involves delivering warheads to a target by a missile which follows a ballistic trajectory and falls on the target under the influence of gravity.

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Kinematics Of A Particle Trajectory

The trajectory is referred to as the curved path followed by an object with respect to its motion in consideration of gravity. It can also be termed projectile motion. Kinematic equations are used to analyze and effectively compute the trajectory followed by particles or objects. The trajectory computations involve the derivations using physical quantities considered relevant to the motion of a particle including, mass m, position r, velocity v, acceleration a.

For instance, an object of mass m moving with distance r witnesses a change in distance referred to as dr. Therefore, velocity is referred to as the change in distance with respect to time and is given by:

v = dr / dt

And acceleration is referred to as the change in velocity of an object with respect to time. Acceleration may be positive, negative, or even zero and is given by:

a = dv / dt

Kinematics of a Particle Trajectory.

Rest: Any object is said to be at a rest position if there is no change in its position with time, with respect to a reference point. The body does not undergo any modification in its position, orientation and pattern when in a state of rest.

Description Of Motion In One Dimension

A bar above any quantity indicates that it is the average value of that quantity. If the acceleration is constant, then equations 1,2 and 3 represent a complete description of the motion. Equation 4 is obtained by a combination of the others. Click on any of the equations for an example.

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What Is Projectile Motion

When a particle is thrown obliquely near the earths surface, it moves along a curved path under constant acceleration directed towards the centre of the earth . The path of such a particle is called a projectile, and the motion is called projectile motion.

In a Projectile Motion, there are two simultaneous independent rectilinear motions:

Acceleration in the horizontal projectile motion and vertical projectile motion of a particle: When a particle is projected in the air with some speed, the only force acting on it during its time in the air is the acceleration due to gravity . This acceleration acts vertically downward. There is no acceleration in the horizontal direction, which means that the velocity of the particle in the horizontal direction remains constant.

Newton’s Laws Of Motion

While Newtons laws of motion may seem obvious to us today, they were considered revolutionary centuries ago. The three laws of motion help us understand how objects behave when standing still, when moving and when forces act upon them. This article describes Sir Newtons three laws and a summary of what they mean.

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What Is Relative Motion Explain With Example

In everyday life, when we measure the velocity of an object, the reference frame is taken to be the ground or the earth. For example, if you are travelling in a train and the train is moving at a speed of 100 km/hr, then your speed according to another passenger sitting on that train is zero.

What is relative velocity in physics?

: the vector difference between the velocities of two bodies : the velocity of a body with respect to another regarded as being at rest compare relative motion.

How do you find relative velocity?

The velocity of the object A relative to the object B can be given as,

What is difference between motion and relative motion?

Motion, as you said, is change in position with respect to time but the definition of relative motion you gave is not really correct. Relative motion is the change in position with respect to a point in space with time. In fact, relative motion and motion are exactly one and the same.