Potential energy is the energy stored in a body or a system by virtue of its position in a field of force or by its configuration. Potential energy is also called mutual energy or energy of configuration. It is measured by the amount of work that a body or system can do in passing from … Read more
The energy produced by mechanical means is called mechanical energy. It has two forms: (i) Kinetic energy (ii) Potential energy. Kinetic energy The energy possessed by a body by virtue of its motion is called its kinetic energy. A moving object can do work. The amount of work that a moving object can do before … Read more
As W = FS ∴ 1 unit work = 1 unit force × 1 unit distance Thus, unit work is the amount of work done when a unit force displaces a body through a unit distance in the direction of the force. Absolute units of work. Work done is said to be one absolute unit … Read more
Every measurement is done with the help of some instrument. While making the measurement, some uncertainty gets introduced in the measurement. As a result, the measured value is always somewhat different from the actual or true value. The error in a measurement is equal to the difference between the true value and the measured value … Read more
The order of magnitude of a physical quantity is that power of 10 which is closest to its magnitude. It gives an idea about how big or how small a given physical quantity is. To determine the order of magnitude of a number N, we first express it as N = n × 10x. If … Read more
A complete set of units which is used to measure all kinds of fundamental and derived quantities is called a system of units. Some of the commonly used systems of units are as follows : (i) cgs system: It was set up in France. It is based on centimetre, gram and second as the fundamental … Read more
Mass: The mass of a body is the quantity of matter contained in it. It is a basic property of matter. It does not depend on the temperature, pressure or location of the body in space. The SI unit of mass is kilogram (kg). Weight: The weight of a body is the force with which … Read more
Laser is used for this method. The word laser stands for light amplification by stimulated emission of radiation. Laser is a source of very intense, highly monochromatic (of one wavelength) and highly directional beam of light. A laser beam is sent towards the moon and its reflected pulse is received. If ‘t’ is the time … Read more
The standard amount of a physical quantity chosen to measure the physical quantity of the same kind is called a physical unit. Desirable characteristics of a physical unit: 1. It should be well-defined. 2. It should be of convenient size, i.e., neither too small nor too large in comparison with the measurable physical quantity. 3. … Read more
