List of top Physics Questions

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason $R$
Assertion A: Efficiency of a reversible heat engine will be highest at $-273^{\circ} C$ temperature of cold reservoir
Reason R: The efficiency of Carnot's engine depends not only on temperature of cold reservoir but it depends on the temperature of hot reservoir too and is given as $n =\left(1-\frac{T_2}{T_1}\right)$
In the light of the above statements, choose the correct answer from the options given below

A point charge of $10\, \mu C$ is placed at the origin At what location on the $X$-axis should a point charge of $40 \, \mu C$ be placed so that the net electric field is zero at $x=2 \, cm$ on the $X$-axis?

Choose the correct relationship between Poisson ratio $(\sigma)$, bulk modulus $( K )$ and modulus of rigidity $(\eta)$ of a given solid object :

A travelling wave is described by the equation $y(x, t)=[0.05 \sin (8 x-4 t)] m$ The velocity of the wave is : [all the quantities are in SI unit]

The half-life of a radioactive nucleus is 5 years. The fraction of the original sample that would decay in 15 years is:

A car travels a distance of ' $x$ ' with speed $v_1$ and then same distance ' $x$ ' with speed $v_2$ in the same direction The average speed of the car is:

The velocity-time graph of a body moving in a straight line is shown in the figure.

The ratio of displacement to distance travelled by the body in time 0 to 10s is:

From the photoelectric effect experiment, following observations are made Identify which of these are correct
A. The stopping potential depends only on the work function of the metal
B. The saturation current increases as the intensity of incident light increases
C. The maximum kinetic energy of a photo electron depends on the intensity of the incident light
D. Photoelectric effect can be explained using wave theory of light
Choose the correct answer from the options given below:

Force acting on a particle moving along the x - axis is given by F = (2 + 3x)i. The work done by this force from x = 0 to x = 4 m is

As per the given figure, a small ball $P$ slides down the quadrant of a circle and hits the other ball $Q$ of equal mass which is initially at rest Neglecting the effect of friction and assume the collision to be elastic, the velocity of ball $Q$ after collision will be :$\left( g =10 \,m / s ^2\right)$

A train is moving with a speed of $10 m/s$ towards a platform and blows a horn with frequency $400 Hz$. Find the frequency heard by a passenger standing on the platform. Take speed of sound = $310 m/s$.

An ice cube has a bubble inside. When viewed from one side the apparent distance of the bubble is 12 cm. When viewed from the opposite side, the apparent distance of the bubble is observed as 4 cm. If the side of the ice cube is 24 cm, the refractive index of the ice cube is:

A current carrying rectangular loop $P Q R S$ is made of uniform wire The length $P R=Q S=5 \,cm$ and $P Q=R S=100\, cm$ If ammeter current reading changes from $I$ to $2 I$, the ratio of magnetic forces per unit length on the wire $P Q$ due to wire $R S$ in the two cases respectively $\left(f_{P Q}^I: f_{P Q}^{2 I}\right)$ is:

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: When you squeeze one end of a tube to get toothpaste out from the other end, Pascal's principle is observed.
Reason R: A change in the pressure applied to an enclosed incompressible fluid is transmitted undiminished to every portion of the fluid and to the walls of its container.
In the light of the above statements, choose the most appropriate answer from the options given below:

A particle starts with an initial velocity of 10.0 m/s along x-direction and accelerates uniformly at the rate of 2.0 m/s$^2$. The time taken by the particle to reach the velocity of 60.0 m/s is

An object is taken to a height above the surface of earth at a distance $\frac{5}{4} R$ from the centre of the earth Where radius of earth, $R =6400 km$ The percentage decrease in the weight of the object will be

Which of the following statements is not correct in the case of light emitting diodes (LEDs)?
A. It is a heavily doped p-n junction.
B. It emits light only when it is forward-biased.
C. It emits light only when it is reverse-biased.
D. The energy of the light emitted is equal to or slightly less then the energy gap of the semiconductor used.
Choose the correct answer from the options given below:

A planet having mass $9M_e$ and radius $4R_e$, where $M_e$ and $R_e$ are mass and radius of earth respectively, has escape velocity in km/s given by: (Given escape velocity on earth $V_e= 11.2 × 10^3 m/s$)

A bullet of 10 g leaves the barrel of gun with a velocity of 600 m/s. If the barrel of gun is 50 cm long and mass of gun is 3 kg, then value of impulse supplied to the gun will be :

Given below are two statements :
Statement I : The temperature of a gas is $-73^{\circ} C$ When the gas is heated to $527^{\circ} C$, the root mean square speed of the molecules is doubled.
Statement II : The product of pressure and volume of an ideal gas will be equal to translational kinetic energy of the molecules.
In the light of the above statements, choose the correct answer from the options given below:

For a periodic motion represented by the equation y = sin ωt + cos ωt, the amplitude of the motion is

For an amplitude modulated wave the minimum amplitude is 3V, while the modulation index is 60%. The maximum amplitude of the modulated wave is

Choose the correct answer from the options given below:

LIST I		LIST II
A	Planck's constant (h)	1	$\left[ M ^1 L ^2 T ^{-2}\right]$
B	Stopping potential (Vs)	2	$\left[ M ^1 L ^1 T ^{-1}\right]$
C	Work function (ø)	3	$\left[ M ^1 L ^2 T ^{-1}\right]$
D	Momentum (p)	4	$\left[ M ^1 L ^2 T ^{-3} A ^{-1}\right]$

A physical quantity P is given as
$ P = \frac{a^2b^2 }{ c\sqrt{d}} .$
The percentage error in the measurement of a,b, c and d are1%, 2%, 3% and 4% respectively. The percentage error in the measurement of quantity P will be

Statement —I: Electromagnets are made of soft iron.
Statement —II: Soft iron has lower permeability and high retentivity.
Choose the correct option related to statements.