Question
The working of optical instruments like camera, microscope, telescope, etc. having glass lenses is based on a phenomenon of light. Identify the phenomenon.

Answer

  1. Reflection

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

A student plots a graph from his reading on the determination of Young modulus of a metal wire but forgets to put the labels. the quantities on X and Y axes may be respectively:
  1. Weight hung and length increased.
  2. Stress applied and length Increased.
  3. Stress applied and strain developed.
  4. Length increased and the weight hung.
​​​​​​​
In a transformer, the number of turns in primary coil and secondary coil are 5 and 4 respectively. If 240 V is applied on the primary coil, then the ratio of current in primary and secondary coil is
For photoelectric emission, tungsten requires light of 2300 Å. If light of 1800 Å wavelength is incident then emission(a) Takes place(b) Don’t take place(c) May or may not take place(d) Depends on frequency
   
   
While doing his experiment, Millikan one day observed the following charges on a single drop
$(i)\  6.563 \times 10^{-19} \mathrm{C}$
$(ii)\ 8.204 \times 10^{-19} \mathrm{C}$
$(iii)\ 11.50 \times 10^{-19} \mathrm{C}$
$(iv)\ 13.13 \times 10^{-19} \mathrm{C}$
$(v)\ 16.48 \times 10^{-19} \mathrm{C}$
$(vi)\ 18.09\times 10^{-19} \mathrm{C}$
From this data the value of the elementary charge $(e)$ was found to be
The average self-induced emf in a 25mH solenoid when the current in it falls from 0.2A to 0A in 0.01 second, is 
In the photoeletric effect, electrons are emitted:
Gauss's law is true only if force due to a charge varies as
The rate of disintegration at a given instant, is directly proportional to the number of atoms present at that instant. This is the statement of:
Magnetic field intensity is defined as:
Which of the following property of an element never changes?