List of top Physics Questions asked in MHT CET

Four polaroids are placed at an angle \(\theta\) with the optic axis of the preceding one. If unpolarised light of intensity 'I' falls on the first polaroid, the intensity of light transmitted from the fourth polaroid is
\([\cos \theta =X]\)

The thin prism having refracting angle \(10^{\circ }\) is made of glass of refractive index \(1.42\). This prism is combined with another thin prism of glass of refractive index \(1.7\). This combination produces dispersion without deviation. The refracting angle of the second prism is

In the case of the photo-electric effect, which of the following sentences is NOT TRUE?
a. The photo-electrons are emitted only when the frequency of incident radiation is greater than the threshold frequency.
b. There is no time lag between incidence of light and emission of electrons.
c. The rate of photo-electric emission is independent of the intensity of incident radiation.
d. The maximum kinetic energy of emitted photo-electrons depends on the frequency of incident radiation.

An interference is observed due to two coherent sources, A and B, separated by a distance \(4\lambda\) along the Y-axis, where \(\lambda\) is the wavelength of the source. Source B is at the origin. A detector D is moved along the positive X-axis. The number of points on the X-axis, excluding \(x=0\) and \(x\rightarrow \infty\), at which maxima will be observed, is

If the r.m.s. current in an a.c. circuit is \(5\) A, having frequency \(50\) Hz. The value of current \(\frac{1}{300}\) s after its value becomes zero (in A) is
\(\{\sin (\pi /3)=(3)^{0.5}/2\}\)

In a series LCR circuit, the resistance (R), inductive reactance \(X_{L}=2R\) and capacitive reactance \(X_{C}=R\). The impedance of the circuit is

An electron is projected with uniform velocity along the axis of a current carrying long solenoid. Which of the following is true?
a. The electron will be accelerated along the axis.
b. The electron path will be circular about the axis.
c. The electron will experience a force at \(45^{\circ }\) to the axis and hence execute a helical path.
d. The electron will continue to move with uniform velocity along the axis of the solenoid.

A magnetic field induction is changing in magnitude at a constant rate \(\frac{dB}{dt}\). The plane of a circular loop of radius \(r\) of copper wire (mass \(m\) and radius \(a\)) is placed perpendicular to the field. The induced current in the loop is {\(\rho\) = specific resistance, \(\delta\) = density of copper}

A paramagnetic sample shows a net magnetization of \(8\) A/m when placed in an external magnetic field of \(0.6\) T at a temperature of \(4\) K. When the same sample is placed in an external magnetic field of \(0.2\) T at a temperature of \(16\) K, the magnetization (in \(\frac{A}{m}\)) will be

When four inductors of the same inductances L are connected in series, and I is the current passing through the circuit. The energy stored in the circuit is

Two concentric coils, each of radius equal to \(2\pi\) cm are placed at right angle to each other. If \(3\) A and \(4\) A are the currents flowing through the two coils, respectively. The magnetic induction (in Wb/m\({}^{2}\)) at the centre of the coils will be {\(\mu _{0}=4\pi \times 10^{-7}\) SI unit}

The output of a step-down transformer is measured to be \(56\) V when connected to \(14\) W light bulb. The value of peak current is (in A)

In the LCR series circuit, an alternating e.m.f. \(e\) and current \(i\) are given by the equation \(e=100\,\sin (100t)V\) and \(i=100\,\sin \left(100t+\frac{\pi }{3}\right)mA\).
The average power dissipated in the circuit will be
\(\{\sin (\pi /3)=3^{0.5}/2,\ \cos (\pi /3)=1/2\}\)

A charge Q is distributed over the two concentric hollow spheres of radii \(r\) and \(R\) (\(R>r\)) such the surface densities are equal. The potential at the common centre is {\(K=\frac{Q}{4\pi \epsilon _{0}}\), \(\epsilon _{0}\) = permittivity of free space}

Two point charges \(8q\) and \(2q\) are located at \(x=0\) and \(x=L\) respectively. The location of a point on the X-axis from origin, at which the net electric field is zero, is \(x\). Value of \(x\) is equal to

In a potentiometer experiment, the balancing with a cell is at length \(240\) cm. On shunting the cell with a resistance of \(2\ \Omega\), the balancing length becomes \(120\) cm. The internal resistance of the cell is

The positively charged particle is released from the rest in a uniform electric field. The electric potential energy of the charge
a. decreases because the charge moves along the electric field.
b. decreases because the charge moves opposite the electric field.
c. remains constant because the electric field is uniform.
d. increases because the charge moves along the electric field.

The U tube of uniform bore of cross-sectional area A has been set up vertically with open ends facing up. Now M gram of a liquid of density d is poured into it. The column of liquid in this tube will oscillate with a period T. The period is

A train moves towards a stationary observer with speed \(20\) m/s. The train sounds a whistle and its frequency heard by the observer is \(f_{1}\). When the train moves away from the platform at a speed of \(20\) m/s, the frequency heard is \(f_{2}\). If the speed of sound is \(340\) m/s, then \(\frac{f_{2}}{f_{1}}\) is

A pendulum clock is running slow. In order to correct it, we should
a. reduce the amplitude of the oscillation.
b. increase the mass of the bob.
c. reduce the length of the pendulum.
d. take the pendulum at the equator to decrease the value of acceleration due to gravity.

The displacement of a wave is given by \(y=0.004\,\sin (200t-2x)\), in SI units. This wave represents a wave

An ideal mono-atomic gas is heated at constant pressure. The fraction of the total energy applied which increases the internal energy for the gas is

A sonometer wire vibrating in two loops is in resonance with a tuning fork. If tension applied to the string is increased to 16 times the original tension and length of the wire is doubled. It can still be in resonance with the tuning fork provided it vibrates in

A pipe closed at end vibrating in the fourth overtone is in unison with the open pipe vibrating in its fourth overtone. The ratio of \(l_{c}:l_{o}\) is {\(l_{c}\) = vibrating length of closed pipe, \(l_{o}\) = vibrating length of open pipe}

A small steel ball of mass \(m\) and density \(7.85\) g/cm\({}^{3}\) is dropped in a container filled with glycerin (density \(=1.26\) g/cm\({}^{3}\)). Its velocity becomes constant after some time. The viscous force acting on the ball is {\(g\) = acceleration due to gravity}