BCA Semester 1: Physics - Forms of Energy
BCA Semester 1: Physics - Forms of Energy
Q & A
Q(2013): (a) State Law of Conservation of Energy.
(b) Write the names of different forms of energy.
Answer:
Law of Conservation of Energy: This law states that energy can neither be created nor be destroyed, but can change form. It means total energy of an isolated system cannot change. The total energy E of a system can change only by amounts of energy that are transferred to or from the system.
i.e. W = △E = △Emech + △Eth + △Eint
where △Emech = change in mechanical energy,
△Eth = change in thermal energy
△Eint = change in other type of internal energy of the system.
(b) Forms of Energy
| Type of Energy | Description |
|---|---|
| Kinetic | Due to motion of a body |
| Potential | Due to position or configuration of the body. |
| Mechanical | Sum of potential and kinetic energy of a body. |
| Electrical | Due to electrical field around a body. |
| Chemical | Due to atoms and molecules of a body |
| Magnetic | Due to magnetic field |
| Nuclear | Due to binding force between sub-atomic particles. |
| Gravitational | Due to gravitational Field |
| Radiant | Due to radiation including light |
| Thermal or Heat | heat energy due to difference in temperature |
| Intrinsic or Internal | Due to mass possessed by an object |
Q (2011): Does kinetic energy of a body depend upon direction of motion? Justify your answer.
Answer: No. Kinetic energy is a scalar quantity. It does not depend on the direction of motion. It depends on mass and magnitude of speed.
