Question

Write an essay that explains the importance of motion to the study of physics. First, describe and define the properties of a moving particle, including position, velocity, and acceleration. Describe how these properties can be measured. Then provide detailed examples of how specific motion affects the world around you. Describe what is moving, and provide detail about the velocity and acceleration of the object. Where applicable, mention any force involved in the motion. Make sure to discuss at least one example of the motion of a macroscopic object, and two examples of the motion of a microscopic object (molecule, atom, particle).

What is the best way to break this down?

Answer 1

The motion of a particle can be characterized by the properties such as displacement, velocity, acceleration, external forces, etc.

Here, I am explaining all the properties in detail by assuming that the particle is under the action of uniform force F and moving in a linear manner. The position often refers as the displacement in vector form. The position signifies the location x of the particle at some instant of time t. The displacement d defines the change in the distance of the particle in time interval delta t. Suppose initially the particle is at position x at t=0 and moves to y at some time t then the displacement is given as

d=y-x.

The velocity is usually symbolizes by v and it is defined as the rate of change of displacement with time t and it is a vector quantity.

v=(change in displacement)/ time.

The acceleration is defined as the rate of change of velocity with time t and is denoted by a.

a=(change in velocity)/time.

We can describe in all the parameters in the differential form as well. If x denotes the displacement then velocity can be given as

The corresponding acceleration a

Various systems can be used to measure these quantities such as CGS, MKS, SI. But usually we prefer SI system to measure these physical quantities. The position is measured in meters, velocity in meters/seconds (m/s) and the acceleration is in m/s² .

The motion is strongly affected by the force acted upon it as it gets cleared by the Newton's second law of motion according to which force F= mass x acceleration. For example if a feather of mass m is falling from the top of building having height h then it will be acted upon by various forces such as gravitational force, air drag, etc and suppose it reaches the floor at some time t while the same feather is thrown from the same building but in vacuum then it will experience only the gravitational pull and will reach the floor faster. So in daily life the forces which are around plays a great role to influence our life.

Onn the microscopic level, I am discussing the atom which is characterized by the nucleus (containing neutrons and protons) and the electrons which are revolving in shell. It is said that the atom is neutral it is because it carries the equal number of protons (positively charge) and electrons (negatively charge). We know that the charged particles possess electrostatic force so the atom must collapse to the attractive nature of this force but atom is spherical in shape it is because of the balancing of the centripetal force (as the electrons are revolving in a shell) with the electrostatic force.

On similar lines the second example on microscopic level can be explained for nucleus as mentioned nucleus is composed of protons (positively charged) and the neutrons (no charge) particles. We know the same charges repel each other so they must not retain in nucleus. But in this case stronger force called as nuclear force exists and it overcomes the electrostatic force of repulsion leading to the binding of nucleons in nucleus.

These microscopic particles which are bounded by such strong forces can only be broken down if they are probed by a beam of high energy microscopic particles such as electrons, etc.