Physics questions
20027 published questions with worked solutions.
- The coefficient of absorption of the surface of a body is 0.68. When 100 calories of heat are incident on the body 27 calories...
- An athermanous metal plate has the coefficient of absorption 0.65. Its coefficient of reflection is:
- Heat is incident at the rate of 10 W on an opaque body having emissivity 0.8. Find the quantity of radiant heat reflected by it...
- The coefficients of absorption and reflection of the surface of a thin plate are 0.74 and 0.22 respectively. If 150 J of radiant...
- Out of 10 J of radiant energy incident on a surface, the energy absorbed by the surface is 2 J and the energy reflected is 7 J....
- If an athermanous body absorbs 20 % of the incident radiant energy, then reflection coefficient of the body is
- The coefficients of absorption and reflection of the surface of a body are 0.70 and 0.25 respectively. If 200 calories of radiant...
- The coefficients of absorption and transmission of the body are 0.50 and 0.25 respectively. If 200 calories, of radiant heat is...
- Black body is defined as the body
- Which of the following body emits more heat
- Perfectly black body appears black in colour because
- Emissivity of perfectly black body is
- A metal ball has black spots which is high heated and then kept in dark room. After this.
- When a perfect black body is heated, it emits thermal radiation of
- The best ideal black body is
- Which of the following will radiate heat to a large extent?
- If the temperature of a perfectly black body increases two times then the rate of radiation of the body also increases by
- The amount of heat energy radiated per second by a surface depends upon
- SI unit of emissive power is
- A body, which emits radiations of all possible wavelengths, is known as