MAH-MHT CET (PCM/PCB) entrance exam Question Bank Solutions for Physics

A student connected the circuit as shown in the figure to determine the internal resistance of a cell E1 by potentiometer (E > E1). He is unable to obtain the null point because ______.

In a potentiometer experiment when three cells A, B, C are connected in series the balancing length is found to be 740 cm. If A and B are connected in series, the balancing length is 440 cm and when B and C are connected in series, it is 540 cm. The e.m.f. of A, B, and C cells E_A, E_B, E_C are respectively (in volt) ______

A potentiometer wire is 4 m long and a potential difference of 3 V is maintained between the ends. The e.m.f. of the cell which balances against a length of 100 cm of the potentiometer wire is ______

A potentiometer wire of length 'L' and a resistance 'r' are connected in series with a battery of E.M.F. 'E₀' and a resistance 'r₁'. A cell of unknown E.M.F, 'E' is balanced at a length 'ℓ' of the potentiometer wire. The unknown E.M.F. E is given by ______ 

In the potentiometer experiment, the balancing length with a cell E₁ of unknown e.m.f. is 'ℓ₁' cm. By shunting the cell with resistance R Ω, the balancing length becomes `ℓ_1/2` cm, the internal resistance (r) of a cell is ______

In the potentiometer experiment, cells of e.m.f. E₁ and E₂ are connected in series (E₁ > E₂). the balancing length is 64 cm of the wire. If the polarity of E₂ is reversed, the balancing length becomes 32 cm. The ratio `E_1/E_2` is ______   

Two identical thin metal plates has charge q₁ and q₂ respectively such that q₁ > q₂. The plates were brought close to each other to form a parallel plate capacitor of capacitance C. The potential difference between them is ______.

Consider a light ray travelling in air is incident into a medium of refractive index `sqrt(2"n")`. The incident angle is twice that of refracting angle. Then, the angle of incidence will be ______.

The refracting angle of a prism is A and refractive index of the material of the prism is cot (A/2). Then the angle of minimum deviation will be ______.

What will be the effect on the root mean square velocity of oxygen molecules if the temperature is doubled and the oxygen molecule dissociates into atomic oxygen?

A parallel beam of light of wavelength 900 nm and intensity 100 wm^-2 is incident on a surface perpendicular to the beam. The number of photons crossing 1 cm² area perpendicular to the beam in one second is ______

Two cells of same emf but different internal resistances r₁ and r₂ are connected in series with a resistance R. The value of resistance R, for which the potential difference across second cell is zero, is ______.

If you are provided a set of resistances 2Ω, 4Ω, 6Ω and 8Ω. Connect these resistances so as to obtain an equivalent resistance of `46/3`Ω.

Which is the correct ascending order of wavelengths?

A cell of internal resistance r is connected across an external resistance nr. Then the ratio of the terminal voltage to the emf of the cell is ______.

Two trains are moving towards each other with speeds of 20m/s and 15 m/s relative to the ground. The first train sounds a whistle of frequency 600 Hz. The frequency of the whistle heard by a passenger in the second train before the train meets, is ______. (the speed of sound in air is 340 m/s) 

A ray of light is incident normally on a glass slab of thickness 5 cm and refractive index 1.6. The time taken to travel by a from source of slab is same as to travel through glass slab. The distance of source from the surface is ______.

A string is vibrating in its fifth overtone between two rigid supports 2.4 m apart. The distance between successive node and antinode is ______.

A mass is suspended from a vertical spring which is executing S.H.M. of frequency 5 Hz. The spring is unstretched at the highest point of oscillation. Maximum speed of the mass is ______. [acceleration due to gravity g = 10 m/s²]

The frequencies for series limit of Balmer and Paschen series respectively are 'v₁' and 'v₃'. If frequency of first line of Balmer series is 'v₂' then the relation between 'v₁', 'v₂' and 'v₃' is ______.