List of top Physics Questions asked in MHT CET

A transverse displacement of vibrating string is \( y = 0.06 \sin\left(\frac{2 \pi}{3} x\right) \cos(120 \pi t) \). If the mass per unit length of a string is \( 4 \times 10^{-2} \) kg/m, then the tension in the string will be

In common emitter mode of a transistor, the current gain is 8. The input impedance is 25kΩ and load resistance is 75kΩ. The power gain is

Two strings 'X' and 'Y' of a guitar produces a beat frequency of 6 Hz. When the tension of the string 'Y' is increased, the beat frequency is found to be 4 Hz. If the frequency of string 'X' is 300 Hz, then the original frequency of string 'Y' is

The electric field intensity on the surface of a solid charged sphere of radius \( r \) and volume charge density \( \sigma \) is \( (\varepsilon_0 = \text{permittivity of free space}) \)

If a black body at 400 K surrounded by atmosphere at 300 K has rate of cooling \( \propto T^4 \), the same body at 900 K, surrounded by same atmosphere, will have rate of cooling nearly

In the following combination of logic gates, the output \( Y \) can be written in terms of inputs \( A \) and \( B \) as

A conducting ring of certain resistance is falling towards a current carrying straight long conductor. The ring and conductor are in the same plane. Then

If the charge on the capacitor is increased by 3C, the energy stored in it increases by 21%. The original charge on the capacitor is

The r.m.s. speed of gas molecules at 800 K will be

An electron moves in Bohr orbit. The magnetic field at the centre is proportional to

A simple pendulum oscillates with an angular amplitude \( \theta \). If the maximum tension in the string is 4 times the minimum tension then the value of \( \theta \) is

An alternating e.m.f. having voltage \( V = V_0 \sin \omega t \) is applied to a series L-C-R circuit. Given \( X_L - X_C = R \), the r.m.s. value of the potential difference across the capacitor will be

A Carnot engine has efficiency \( \frac{1}{3} \). It becomes \( \frac{1}{3} \), when the temperature of sink is lowered by 57 K. The temperature of the source is

Hot water cools from 80°C to 60°C in 1 minute. In cooling from 60°C to 50°C it will take (room temperature = 30°C)

An ideal inductor of \( \frac{1}{2} \, \text{H} \) is connected in series with a \( 300 \, \Omega \) resistor. If a 20 V, 200 Hz alternating source is connected across the combination, the phase difference between the voltage and current is

Two capillary tubes of same diameter are kept vertically in two liquids whose densities are in the ratio \( 4:3 \). If their surface tensions are in the ratio \( 6:5 \), the ratio of heights \( \left( \frac{h_1}{h_2} \right) \) of liquids in the two capillary tubes is (Their angle of contacts are same)

A coil having 9 turns carrying current produces magnetic field \( B_1 \) at the centre. Now that coil is rewound into 3 turns carrying same current. Then magnetic field at the centre \( B_2 \) is

A conveyor belt is moving with constant velocity \( V \). Sand is being dropped on the belt at the rate of \( M \, \text{kg/s} \). The force necessary to keep the belt moving with a constant velocity \( V \, \text{m/s} \) will be

According to Huygen’s wave theory of light, which one of the following statements is not correct?

When photons of energies twice and thrice the work function of a metal are incident on the metal surface one after other, the maximum velocities of the photoelectrons emitted in the two cases are \( V_1 \) and \( V_2 \) respectively. The ratio \( V_1 : V_2 \) is

In air, a charged soap bubble of radius \( R \) breaks into 64 small soap bubbles of equal radius \( r \). The ratio of mechanical force per unit area of big soap bubble to that of a small bubble is

A coil is wound on a core of rectangular cross section. If all the linear dimensions of core are increased by a factor 3 and number of turns per unit length of coil remains same, the self inductance increases by a factor

A body starts from rest and moves with a uniform acceleration. The ratio of the distance covered by the body in the \( n^{th} \) second of its motion to the total distance travelled in \( n \) seconds is

A ray of light travelling through rarer medium is incident at a very small angle \( \theta \) on a glass slab and after refraction its velocity is reduced by 20%. The angle of deviation is