Question
List the salient features of heat radiations.

Answer

Heat radiations :
  1. Can travel through vacuum.
  2. Travel with a velocity of $3 \times 10^9m/sec$.
  3. Travel in straight lines.
  4. Obey the laws of reflection.
  5. Does not heat the medium on its way.
  6. Reduce their intensity with square of the distance from source.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

It is well known that a raindrop falls under the influence of the downward gravitational force and the opposing resistive force. The latter is known to be proportional to the speed of the drop but is otherwise undetermined. Consider a drop of mass $1.00 g$ falling from a height $1.00 \ km$. It hits the ground with a speed of $50.0\ m s ^{-1}. (a)$ What is the work done by the gravitational force? What is the work done by the unknown resistive force?
Two vessels of the same size are at the same temperature. One of them holds $1kg$ of $H_2$ gas and the other holds $1\ kg$ of $N_2$ gas.
  1. Which of the vessels contains more molecules?
  2. Which of the vessels is under greater pressure and why?
  3. In which vessel is the average molecular speed greater? How many times greater?
A mercury drop of radius 1.0 cm is sprayed into $10^6$ droplets of equal size. Calculate the energy expended. The surface tension of mercury $=32 \times 10^{-2} Nm ^{-1}$.
 A highway motorist travels at a constant velocity of $45 km / h ^{-1}$ in a $30 km / h ^{-1}$ zone. A motor-cyclist police officer has been watching from behind a bill board and at the same moment the speeding motorist passes the bill board, the police officer accelerates uniformly from rest to overtake her. If the acceleration of the police officer is $10 km / h ^{-2}$, how long does he take to reach the motorist?
Does focal length of a lens depend on the colour of the light used? Does focal length of a mirror depend on the colour?
A hollow sphere of radius R lies on a smooth horizontal surface. It is pulled by a horizontal force acting tangentially from the highest point. Find the distance travelled by the sphere during the time it makes one full rotation.
Calculate the power of a motor which is capable of raising of water in 5 min from a well 120m deep.
What are the basic requirements of a cooking utensil in respect of specific heat, thermal conductivity and coefficient of expansion?
What is concurrent force? What is the necessary condition for the balance of concurrent forces?
A celsius and fahrenheit thermometer are put in an hot bath. The reading of fahrenheit thermometer is $\frac{3}{2}$ times the reading of celsius thermometer. What is the temperature of bath on celsius, fahrenheit and kelvin's scales.