physicsuniversalclasses

 Introduction:     When an object is in motion, its position changes with time. But how fast is the position changing with time ? To describe this, we define then quantity is speed.         If an object moving along the straight line covers equal distances in equal intervals of time, i.e object moving with uniform motion along a straight line.      If an object moving along a straight line covers unequal distances in equal intervals of time or equal distances in unequal intervals of time, then it is said to be moving with non-uniform motion. Ex: 1. Motion of a freely falling body. 2. Motion of a body thrown vertically upwards. Speed :    "The distance travelled by a body in unit time" is called it's speed.    It is a scalar quantity. It shows only magnitude but no specified direction.        S.I unit is m/s        C.G.S unit is cm/s.   1 km/hr = 5/18   m/s   1 m/s   =  18/5  km/hr Average speed :     To describe the rate of motion over the actual path. We introduce anothe

This theory discuss in the following link my youtube channel   Introduction:               Early you learnt that motion is change in position. In order to specify position, we need to use a reference point and a set of axes.            Seemingly rest and motion are quite opposite to each other. However, the following example will prove that sometimes it becomes very difficult to say whether a body is at rest or is in a state of motion.         For example, imagine that you are travelling by a bus. If you compare your position with respect to the surroundings outside the bus, such as trees, fields, houses, etc., you will find that your position is changing with respect to them. Hence, you are in a state of motion.                 However, if you compare your position with respect to the surroundings inside the bus, i.e., passengers, walls and roof of the bus, you will find that your position is not changing with respect to the surroundings, and hence, you are at rest.             If you

Introduction:           Many objects that physicists study from atoms to galaxies are in motion. Motion may be orderly or random, steady or intermittent or even a confusing mixture of these. Motion is common to everything in the universe. We well, run and ride a bicycle. Even when we are sleeping , air moves into and out of our lungs and blood flows in arteries and veins. We see leaves falling from trees and water flowing down a dam. Automobiles and planes carry people from one place to the other. The earth rotates once every twenty - four hours and revolves around the sun once in a year. The sun itself is in motion in the milky way, which is again moving within its local group of galaxies.  Motion is change in position of an object with time. How does the position change with time? In this chapter, we shall learn how to describe motion. For this, we develop the concepts of velocity and acceleration. Study of motion of objects along a straight line also known as rectilinear motion. For

 Introduction :     The terms work , energy and power are frequently used in everyday language.  For example , A woman carrying water from a well to her house is said to be working. In a drought affected region she may be required to carry it over large distances. If , she can do so , she is said to have a large stamina or energy. Energy is thus the capacity to do work. The term power is usually associated with speed.  In physics we shall define these terms very precisely. Work :  work is related to force and the displacement over which it acts. Consider a constant force F acting on an object of mass m. The object undergoes a displacement d in the positive  x - direction as shown in Fig. The work done by the force can be defined as  " the product of magnitude of displacement and component of force along the displacement ". work is a scalar quantity. The S.I unit of work is joule(  J ) and C.G.S   unit of work is erg.  work done can be calculated by following three ways. 1. wo