Question
Transformer is based on the principle of:
✓
Answer
(d)None of the above
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
Light with an energy flux of $20W/cm^2$ falls on a non$-$reflecting surface at normal incidence. If the surface has an area of $30\ cm^2$. the total momentum delivered $($for complete absorption$)$ during $30$ minutes is:
→The resistance in the following circuit is increased at a particular instant. At this instant the value of resistance is $10 \Omega$. The current in the circuit will be now
→When X-rays, Y-rays and microwaves travel in vacuum, their :
In V-I characteristic of a p-n junction, reverse biasing results in:
Assertion : Blue colour of sky appears due to scattering of blue colour.
Reason : Blue colour has shortest wave length in visible spectrum.(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.(c) If assertion is true but reason is false.(d) If the assertion and reason both are false.
Reason : Blue colour has shortest wave length in visible spectrum.(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.(c) If assertion is true but reason is false.(d) If the assertion and reason both are false.
A long wire carries a steady current. It is bent into a circle of one turn and the magnetic field at the centre of the coil is $B .$ It is then bent into a circular loop of $n$ turns. The magnetic field at the centre of the coil will be
→A element used for radioactive carbon dating for more than 5600 years is(a) C - 14 (b) U - 234(c) U - 238(d) Po - 94
An observer on earth observes that wave length of spectral line in spectrum of a milky way shifts towards red end of spectrum. According to the observer, the milky-way is:
Assertion : Light is produced in gases in the process of electric discharge through them at high pressure.
Reason : At high pressure electrons of gaseous atoms collide and reach and excited state.(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.(c) If assertion is true but reason is false.(d) If the assertion and reason both are false.
Reason : At high pressure electrons of gaseous atoms collide and reach and excited state.(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.(c) If assertion is true but reason is false.(d) If the assertion and reason both are false.
The formula for displacement $\left( I _d\right)$ is :
→