List of top Physics Questions

A parallel plate capacitor has charge $ 5 \times 10^{-6} \, C $. A dielectric slab is inserted between the plates and almost fills the space between the plates. If the induced charge on one face of the slab is $ 4 \times 10^{-6} \, C $ then the dielectric constant of the slab is ____.
Which one of the following forces cannot be expressed in terms of potential energy?
An object with mass $ 500 \, g $ moves along x-axis with speed $ v = 4\sqrt{x} \, m/s $. The force acting on the object is :
A helicopter flying horizontally with a speed of $ 360 \, km/h $ at an altitude of $ 2 \, km $, drops an object at an instant. The object hits the ground at a point O, $ 20 \, s $ after it is dropped. Displacement of 'O' from the position of helicopter where the object was released is :
(use acceleration due to gravity $ g = 10 \, m/s^2 $ and neglect air resistance)

A transparent block A having refractive index $ \mu_2 = 1.25 $ is surrounded by another medium of refractive index $ \mu_1 = 1.0 $ as shown in figure. A light ray is incident on the flat face of the block with incident angle $ \theta $ as shown in figure. What is the maximum value of $ \theta $ for which light suffers total internal reflection at the top surface of the block ?

A dipole with two electric charges of $ 2 \, \mu C $ magnitude each, with separation distance $ 0.5 \, \mu m $, is placed between the plates of a capacitor such that its axis is parallel to an electric field established between the plates when a potential difference of $ 5 \, V $ is applied. Separation between the plates is $ 0.5 \, mm $. If the dipole is rotated by $ 30^\circ $ from the axis, it tends to realign in the direction due to a torque. The value of torque is :

Match List-I with List-II.

Choose the correct answer from the options given below :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A) : Magnetic monopoles do not exist.
Reason (R) : Magnetic field lines are continuous and form closed loops.
In the light of the above statements, choose the most appropriate answer from the options given below :
The equation of a wave travelling on a string is $ y = \sin[20\pi x + 10\pi t] $, where x and t are distance and time in SI units. The minimum distance between two points having the same oscillating speed is :
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A) : Refractive index of glass is higher than that of air.
Reason (R) : Optical density of a medium is directly proportionate to its mass density which results in a proportionate refractive index.
In the light of the above statements, choose the most appropriate answer from the options given below :

Consider the following logic circuit.

The output is Y = 0 when :

A capillary tube of radius 0.1 mm is partly dipped in water (surface tension 70 dyn/cm and glass water contact angle $ \approx 0^\circ $) with $ 30^\circ $ inclined with vertical. The length of water risen in the capillary is ____ cm. (Take $ g = 9.8 $ m/s$^2 $)
A mirror is used to produce an image with magnification of $ \frac{1}{4} $. If the distance between object and its image is 40 cm, then the focal length of the mirror is ____.
The helium and argon are put in the flask at the same room temperature (300 K). The ratio of average kinetic energies (per molecule) of helium and argon is : (Give : Molar mass of helium = 4 g/mol, Molar mass of argon = 40 g/ mol )
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : The radius vector from the Sun to a planet sweeps out equal areas in equal intervals of time and thus areal velocity of planet is constant.
Reason (R) : For a central force field the angular momentum is a constant. In the light of the above statements, choose the most appropriate answer from the options given below :
If \( B = 400\sqrt{2} \sin(\omega t - kx) \), find the peak value of the magnetic field of the electromagnetic wave.
A stone is dropped from a height of 45 m. What is the time taken for the stone to reach the ground?
A current of 2 A flows through a resistor for 10 minutes. What is the total charge that flows through the resistor?
A convex lens has a focal length of 10 cm. What is the magnification produced when the object is placed 30 cm from the lens?
A body of mass 10 kg is moving with a speed of 5 m/s. What is the momentum of the body?
What is the resistance of a conductor if the potential difference across it is 12 V and the current flowing through it is 3 A?
The potential energy of a body at a height of 10 meters is 200 J. What is its mass? (Take \( g = 10 \, \text{m/s}^2 \))
A body of mass 2 kg is moving with a velocity of 3 m/s. What is its kinetic energy?
What is the focal length of a lens if its power is +2 D?
A 0.5 m long solenoid has 100 turns and carries a current of 3A. What is the magnetic field at the center of the solenoid?