Physics Mock Test-5

The velocity v of waves produced in water depends on their wavelength λ, the density of water d and acceleration due to gravity g. These quantities are related as (where K is a dimensionless constant)

SI unit of magnetic dipole moment is

A 50Hz AC signal is applied in a circuit of inductance of (1/π)H and resistance 2100Ω. The impedance offered by the circuit is

A galvanometer has a resistance 50Ω. A resistance of 5Ω is connected parallel to it. Fraction of the total current flowing through galvanometer is

A deutron is bombarded on ₈O¹⁶ nucleus and α-particle is emitted. The product nucleus is

Two spherical nuclei have mass numbers 216 and 64 with their radii R₁ and R₂, respectively. The ratio, R₁/R₂ is equal to

A 36 Ω galvanometer is shunted by resistance of 4 Ω. The percentage of the total current, which passes through the galvanometer is

A current of 5 A is passing through a metallic wire of cross-sectional area 4×10⁻⁶ m². If the density of charge carriers of the wire is 5×10²⁶ m⁻³, the drift velocity of the electrons will be

An α-particle moves in a circular path of radius 0.83 cm in the presence of a magnetic field of 0.25 Wb m⁻². The de-Broglie wavelength associated with the particle will be

A charged oil drop is suspended in a uniform field at 3×10⁴ V/m so that it neither falls nor rises. The charge on the drop will be (Take the mass of the charge=9.9×10⁻¹⁵ kg and g=10 m/s²)

Electrons with energy 80 keV are incident on the tungsten target of an X-ray tube. The K-shell electrons of tungsten have -72.5 keV energy. The X-rays emitted by the tube contains only

A coil of resistance 10 Ω and an inductance 5 H is connected to a 100 volt battery. The energy stored in the coil is

A short circuited coil is placed in a magnetic field varying with time. Electrical power is dissipated due to the current induced in the coil. If the number of turns were to be quadrupled and the wire radius halved, the electrical power dissipated would be

A n-p-n transistor is connected in common emitter configuration in a given amplifier. A load resistance of 800Ω is connected in the collector circuit and the voltage drop across it is 0.8 V. If the current amplification factor is 0.96 and the input resistance of the circuits is 192Ω,then the voltage gain and the power gain of the amplifier will respectively be

A Zenor diode has a contact potential of 1 V in the absence of biasing. It undergoes Zenor breakdown for an electric field of 10⁶ V/m at the depletion region of p-n junction. If the width of the depletion region is 2.5 μm, what should be the reverse biased potential for the Zenor breakdown to occur?

A capacitor is charged to 200 volt. It has a charge of 0.1 coulomb. When it is discharged, energy liberated will be

A electric dipole is placed at an angle of 30⁰ to a non-uniform electric field. The dipole will experience

If the earth shrink such that its mass does not change but radius decreases to one quarter of its original value then one complete day will take

The earth is assumed to be a sphere of radius R. A platform is arranged at a height R from the surface of the earth. The escape velocity of a body from this platform is fv, where v is its escape velocity from the surface of the Earth. The value of f is

A body of mass 1.0 kg is falling with an acceleration of 10 ms⁻². Its apparent weight will be (g=10 ms⁻²)

A plumb line is suspended from a ceiling of a car moving with horizontal acceleration of ɑ. What will be the angle of inclination with vertical?

A bar magnet is hung by a thin cotton thread in a uniform horizontal magnetic field and is in equillibrium state. The energy required to rotate it by 60⁰ is W. Now the torque required to keep the magnet in this new position is

A charged particle of mass m and charge q moves along a circular path of radius r that is perpendicular to a magnetic field B. The time taken by the particle to complete one revolution is

Maximum range for a projectile motion is given as R. The maximum height will be

A simple pendulum oscillates in a vertical plane. When it passes through the mean position, the tension in the string is 3 times the weight of the pendulum bob. What is the maximum displacement of the pendulum string with respect to the vertical?

Three particles A,B and C are thrown from the top of a tower with the same speed. A is thrown straight up, B is thrown straight down and C is thrown horizontally. They hit the ground with speed V(A),V(B) and V(C) respectively.

A body starts from rest with an acceleration of 2 m/s². After 5 second, the direction of acceleration reverses again for 5 second. The displacement is

Two discs of moment of inertia I₁ and I₂ and angular speeds ?￢ﾂﾁ and ?￢ﾂﾂ are rotating along collinear axes passing through their centre of mass and perpendicular to their plane. If the two are made to rotate jointly along the same axis, the rotational K.E. of system will be

A solid sphere, a hollow sphere and a ring are released from top of an inclined plane (frictionless) so that they slide down the plane. Then maximum acceleration down the plane is for (no rolling)

Two particles P and Q start from origin and execute simple harmonic motion along X-axis with same amplitude but with periods 3 sec and 6 sec respectively. The ratio of velocities of P and Q when they meet is

A particle doing SHM has amplitude=4 cm and time period = 12 sec. The ratio between times taken by it in going from its mean position to 2 cm and from 2 cm to extreme position is

The value of Poisson’s ratio lies between

A glass flask weighing 390 g having internal volume 500 cc just floats when half of it is filled with water. Specific gravity of the glass is

After 300 days, the activity of a radioactive sample is 5000 dps (disintegration per second). The activity becomes 2500 dps after another 150 days. The initial activity of the sample (in dps) is

A sample of radioactive element has a mass of 10 gram at an instant t=0. The approximate mass of this element in the sample after two mean lives is

An object is seen through a simple microscope of focal length 12 cm. What will be the angular magnification produced, if the image is formed at the near point of the eye which is 25 cm away from it?

A thin convex lens of refractive index 1.5 has 20 cm focal length in air. If the lens is completely immersed in a liquid of refractive index 1.6, then its focal length will be

At 0⁰C, 15 gm of ice melts to form water at 0⁰C. The change in entropy is

If a given volume of water in a 220V heater is boiled in 5 min, then same volume of water in 110V heater can be boiled in what time interval?

A linear aperture whose width is 0.02 cm is placed immediately in front of a lens of focal length 60 cm. The aperture is illuminated normally by a parallel beam of wavelength 5×10⁻⁵ cm. The distance of the first dark band of the diffraction pattern from the centre of the screen is

In Young’s double slit experiment, the phase difference between the two waves reaching at the location of the third dark fringe is

Two closed pipes produce 10 beats per second when emitting their fundamental nodes. If their lengths are in the ratio of 25:26, then their fundamental frequencies in Hz are

The frequency of fundamental tone in an open organ pipe of length 0.48 m is to 320 Hz. Speed of sound is 320 m/s. Frequency of fundamental tone in closed organ pipe will be

A force of 10N is applied on a body for 3 sec and the corresponding displacement 6 m. The power of the source is

A neutron is moving with a velocity u.It collides head on and elastically with an atom of mass number A. If the initial kinetic energy of the neutron be E. How much kinetic energy will be retained by neutron after collision?