MCQ
Good absorbers of heat are
- APoor emitters
- BNon-emitters
- ✓Good emitters
- DHighly polished
✓
Answer
Correct option: C.
Good emitters
c
(c)Good absorbers are always good emitters of heat.
(c)Good absorbers are always good emitters of heat.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
In a parallel beam of white light is incident on a converging lens, the colour which is brought to focus nearest to the lens is
A plano-convex thin lens is used to obtain the image of a point object $O$ on the screen $S$ as shown in figure. The thickness of the lens in the middle is $0.5\ cm$ and refractive index of the material of the lens is $1.5$ . If the separation $D$ between the object and the screen is to be minimum, then the aperture diameter of the lens should be.....$cm$ (consider lens as thin)
→An electric dipole is placed at an angle of $30^{\circ}$ with an electric field of intensity $2 \times 10^5\,NC ^{-1}$. It experiences a torque equal to $4\,Nm$. Calculate the magnitude of charge on the dipole, if the dipole length is $2\,cm$.
→A conductor of length $l$ and mass $m$ can slide along a pair of vertical metal guides connected by a resistance $R,$ as shown in fig. Friction, resistance of conductor and guide rails are negligible. There exist a horizontal uniform magnetic field of strength $B$ normal to the plane of the page and is directed outward. The terminal speed of fall under the unfluence of gravity is, then :-
→In Young's double slit experiment, carried out with light of wavelength $5000$ $A$, the distance between the slits is $0.3 \mathrm{~mm}$ and the screen is at $200 \mathrm{~cm}$ from the slits. The central maximum is at $x=0 \mathrm{~cm}$. The value of $\mathrm{x}$ for third maxima is ............. $\mathrm{mm}$.
→Find the acceleration of particle at $x = 5\,m$ with the help of graph. where $v-$ velocity and $x-$ displacement
→A vibrating string of certain length $l$ under a tension $T$ reasonates with a mode corresponding to the first overtone (third harmonic) of an air column of length $75$ $cm$ inside a tube closed at one end. The string also generates $4$ beats per second when excited along with a tuning fork of frequency $n$. Now when the tension of the string is slightly increased the number of beats reduces to $2$ per second. Assuming the velocity of sound in air to be $340$ $m/s$, the frequency $n$ of the tuning fork in $Hz $ is
→Two plane mirror are inclined to one another at an angle of $60^o$ . A ray is incident on mirror $M_1$ at an angle $i$. The reflected ray from mirror $M_1$ is shown in figure. The angle of incidence $i$ is
→$Assertion :$ When a glass of hot milk is placed in a room and allowed to cool, its entropy decreases.
$Reason :$ Allowing hot object to cool does not violate the second law of thermodynamics.
→$Reason :$ Allowing hot object to cool does not violate the second law of thermodynamics.
At room temperature, a $P-$ type semiconductor has
→