At a high temperature,a body emits radiation of wavelengths $\lambda_1, \lambda_2, \lambda_3,$ and $\lambda_4$ only. At a lower temperature,which of the following wavelengths will it absorb?

$A$ piece of blue glass heated to a high temperature and a piece of red glass at room temperature are taken inside a dimly lit room. Then:

The following figure shows two air-filled bulbs connected by a $U$-tube partly filled with alcohol. One bulb is painted black and the other is painted white (or silver/shiny). What happens to the levels of alcohol in the limbs $X$ and $Y$ when an electric bulb placed midway between the two bulbs is lighted?

$A$ body,which emits radiations of all possible wavelengths,is known as

If a vessel with black spots is heated to a very high temperature and then taken into a dark room,then:

Which of the following is best close to an ideal black body?