Exams › NEET › Physics

A piece of iron is heated in a flame. It first becomes dull red then becomes reddish yellow and finally turns to white hot. The correct explanation for the above observation is possible by using:

1. Wien’s displacement law
2. Kirchhoff’s law
3. Newton’s law of cooling
4. Stefan’s law

Correct answer: Wien’s displacement law

Solution

The color change of the heated iron corresponds to the shift in the peak wavelength of emitted radiation as its temperature increases, which is explained by Wien's displacement law.

Related NEET Physics questions

• An instrument used to measure high temperature is
• Ocean currents are caused by the setting up of in water
• For the same mass, which one of the following has the maximum thermal capacity?
• The excess temperature of a body falls from \( 12^{\circ} \mathrm{C} \) to \( 6^{\circ} \mathrm{C} \) in 5 minutes, then the time to fall the excess temperature from \( 6^{\circ} \mathrm{C} \) to \( 3^{\circ} \mathrm{C} \) is (assume the Newton's cooling is valid)
• Bunty mixed 440 gm of ice at \( 0^{\circ} \mathrm{C} \) with \( 540 \mathrm{gm} \) of water at \( 80^{\circ} \mathrm{C} \) in a bowl. Then what would remain after sometime in the bowl?
• Mercury boils at \( 356^{\circ} \mathrm{C} \). However mercury thermometers are made such that they can measure temperatures up to \( 500^{\circ} \mathrm{C} \). This is done by :

⚔️ Practice NEET Physics free + battle 1v1 →