List of top Physics Questions

If binding energy per nucleon of deuteron and \( \alpha \)-particle are 1.25 MeV and 7.4 MeV respectively, then find the value of \( Q \) in the following reaction: 

\[2  ^1_1H \rightarrow 2  ^4_2He + Q\]

Unit of \( \frac{1}{\mu_0 \epsilon_0} \) is:

A square loop of each side 10 cm and having resistance 0.5 $\Omega$ is kept vertical in east-west plane. The uniform magnetic flux density of 0.01 Tesla is established across the plane along north-east direction. After 0.70 sec, the magnetic field is reduced to zero with uniform rate. Calculate the following:
(i) the initial and final magnetic flux,
(ii) the induced e.m.f.,
(iii) the induced current,
(iv) the induced charge.
Write the nature of path of a charged particle moving:
(i) along the electric field,
(ii) perpendicular to the electric field,
(iii) perpendicular to the magnetic field,
(iv) along the magnetic field,
(v) along the combination of electric field and magnetic field acting mutually perpendicular to each other.
Establish the formula for the force acting between two parallel current carrying straight wires of infinite length. Explain when and why the force between both current carrying conductors becomes
(i) attractive and
(ii) repulsive.
The refractive index for material of prism having refracting angle $60^\circ$ is $1.414$. For light incident on prism in minimum deviation position, calculate:
(i) Angle of minimum deviation,
(ii) Angle of incidence,
(iii) Angle of refraction,
(iv) Angle of emergence. Also draw ray diagram.
Compare astronomical telescope with compound microscope. Can a telescope be used as a microscope and vice-versa? Explain with reason.
State, explain and compare features of
(i) Gauss’s law in electrostatics and
(ii) Ampere’s circuital law in magnetostatics.
What are eddy currents? Give two applications of it.
What is electromagnetic induction? Give names of two devices based on it.
In the given circuit, find (i) voltage across resistance, (ii) current in the circuit, (iii) phase difference between voltages across inductance and capacitance.
Explain why:
[(i)] Lighter nuclei fuse together to form a heavy nucleus.
[(ii)] A heavy nucleus splits into two lighter nuclei.
[(iii)] Energy is released in both phenomenon of nuclear fission and nuclear fusion.
What is $Q$-value of a nuclear reaction? Find (i) nature, (ii) $Q$-value, and (iii) mass defect of nuclear reaction: \[ 2({}^1H^2) \; \longrightarrow \; {}^4He^2 + g \] if the binding energy per nucleon of deuterium and helium are $1.25 \, \text{MeV}$ and $7.2 \, \text{MeV}$ respectively.
Find the resultant intensity of two waves having intensities $9I$ and $4I$ when waves are (i) coherent and (ii) non-coherent.
Draw an energy level diagram for hydrogen atom. Calculate the wavelengths of (i) H$_\alpha$, (ii) H$_\beta$, and (iii) Series limit of Balmer series.
A proton (p) and an $\alpha$-particle are accelerated to the same potential difference. Find the ratio of de Broglie wavelengths associated with proton and $\alpha$-particle.
What are doped semiconductors? Explain the effect of (i) doping and (ii) temperature on the conductivity of semiconductors.
Obtain an expression for (i) potential difference and (ii) capacitance of a parallel plate capacitor filled partly with dielectric material between plates.
A metal has work function of 2.0 eV and is illuminated by monochromatic light of wavelength 5000 \AA. Calculate (i) the threshold wavelength and (ii) the stopping potential.
Two lenses of powers +5D and –3D are placed in contact. Find (i) the focal length and (ii) the power of the combined lens.
Compare the features of (i) forward biased and (ii) reverse biased p-n junction. Mention the nature of biasing in solar cell.
On what factors does the internal resistance of a cell depend?
Draw circuit diagram of Wheatstone’s bridge. Which are its conjugate arms?
What is meant by shunt and mention its one use in electrical circuit?
Show that $\left(\dfrac{\text{Henry}}{\text{Farad}}\right)^{1/2}$ represents resistance.