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Physics · UNITS AND MEASUREMENT
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Physics · Electrostatic Potential
Given below are two statements: Statement I: The formula for electrostatic energy density \( u = \frac{1}{2} \varepsilon_0 E^2 \) is valid only for the uniform electric field between the plates of a parallel plate capacitor. Statement II: The permittivity of a dielectric medium is always smaller than the permittivity of free space. In the light of the above statements, choose the most appropriate answer from the options given below:
Read answer →Physics · PYQ NEET UG 2026
A ray of light with wavelength \( \lambda \) is incident on three different photoelectric cells namely 1, 2 and 3. The threshold wavelength of these photoelectric cells are \( \lambda_1 \), \( \lambda_2 \), and \( \lambda_3 \), respectively and the magnitude of stopping potentials of these cells are \( V_1 \), \( V_2 \) and \( V_3 \), respectively. The relation between \( \lambda \) and threshold wavelengths are \( \lambda_1 < \lambda \), \( \lambda_2 > \lambda \) and \( \lambda_3 \gg \lambda \). The correct option is :
Read answer →Physics · PYQ NEET UG 2022
When light propagates through a material medium of relative permittivity \( \in_r \) and relative permeability \( \mu_r \), the velocity of light, \( \nu \) is given by: (\( c \) – velocity of light in vacuum)
Read answer →Physics · MOTION IN A STRAIGHT LINE
A body starting from rest moves with constant acceleration \( a \). If the time taken by the body to cover successive equal distance segments \( S \) are \( t_1, t_2, t_3 \dots \), then the ratio \( t_1 : t_2 : t_3 \) is:
Read answer →Physics · MOTION IN A STRAIGHT LINE
A bullet entering a wooden block with an initial velocity of \( 100\text{ m s}^{-1} \) comes to rest after penetrating a distance of \( 0.1\text{ m} \). Assuming uniform retardation, what is the magnitude of the deceleration of the bullet?
Read answer →Physics · MOTION IN A PLANE
The position coordinates of a particle moving in the \( x\text{-}y \) plane are \( x(t) = 2t^3 - 3t^2 \) and \( y(t) = t^3 - 12t \) (where \( x, y \) are in metres and \( t \) in seconds). At what non-zero time \( t \) is the \( y \)-component of velocity equal to zero, and what is the speed of the particle at that instant?
Read answer →Physics · PYQ NEET UG 2022
The truth table for the given logic circuit is:Logic Circuit Diagram
Read answer →Physics · PYQ NEET UG 2023
A horizontal bridge is built across a river. A student standing on the bridge throws a small ball vertically upwards with a velocity \( 4\text{ m s}^{-1} \). The ball strikes the water surface after \( 4\text{ s} \). The height of bridge above water surface is (Take \( g = 10\text{ m s}^{-2} \)) :
Read answer →Physics · UNITS AND MEASUREMENT
What is the number of significant figures in the measured length \( 23080\text{ }\mu\text{m} \)?
Read answer →Physics · PYQ NEET UG 2023
A football player is moving southward and suddenly turns eastward with the same speed to avoid an opponent. The force that acts on the player while turning is :
Read answer →Physics · WORK, ENERGY AND POWER
A particle moves along the x-axis under the influence of a conservative force whose potential energy is given by \( V(x) = \alpha x^2 - \beta x \), where \( \alpha \) and \( \beta \) are positive constants. The force \( F(x) \) acting on the particle is:
Read answer →Physics · PYQ NEET UG 2017
A spring of force constant \( k \) is cut into lengths of ratio \( 1:2:3 \). They are connected in series and the new force constant is \( k' \). Then they are connected in parallel and force constant is \( k'' \). Then \( k' : k'' \) is
Read answer →Physics · PYQ NEET UG 2017
The bulk modulus of a spherical object is 'B'. If it is subjected to uniform pressure 'P', the fractional decrease in radius is
Read answer →Physics · LAWS OF MOTION
A stream of water flowing horizontally at a speed of \( 15\text{ m/s} \) pushes against a rigid vertical wall at a steady rate of mass flow equal to \( 20\text{ kg/s} \). Assuming the water comes to rest immediately after striking the wall without rebounding, the force exerted by the water stream on the wall is:
Read answer →Physics · PYQ NEET UG 2026
An ac voltage $V = 220 \sin(2 \times 10^3 t)$ Volt is applied to a series LCR circuit. Then the current amplitude in this circuit is : (Given : $L = 10$ mH, $C = 25$ $\mu$F, $R = 100$ $\Omega$)
Read answer →Physics · LAWS OF MOTION
A block of mass \( m = 4\text{ kg} \) is projected with an initial velocity \( v_0 = 10\text{ m/s} \) along a rough horizontal plane. The block comes to rest after covering a distance of \( d = 25\text{ m} \). Taking \( g = 10\text{ m/s}^2 \), calculate the coefficient of kinetic friction \( \mu_k \) and the rate of work done by friction (power) at time \( t = 1\text{ s} \).
Read answer →Physics · Electrostatic Potential
If an arbitrary constant \( \alpha \) is added to the electrostatic potential energy at every point in space, what will happen to the potential energy difference \( \Delta U = U_P - U_R \) between two points P and R?
Read answer →Physics · PYQ NEET UG 2016(1)
The molecules of a given mass of a gas have r.m.s velocity of \( 200\text{ ms}^{-1} \) at \( 27^\circ\text{C} \) and \( 1.0 \times 10^5\text{ Nm}^{-2} \) pressure. When the temperature and pressure of the gas are respectively, \( 127^\circ\text{C} \) and \( 0.05 \times 10^5\text{ Nm}^{-2} \), the r.m.s. velocity of its molecules in \( \text{ms}^{-1} \) is
Read answer →Physics · PYQ NEET UG 2020
The average thermal energy for mono-atomic gas is: (\( k_B \) is Boltzmann constant and T, absolute temperature)
Read answer →Physics · PYQ NEET UG 2020
A ray is incident at an angle of incidence i on one surface of a small angle prism (with angle of prism A) and emerges normally from the opposite surface. If the refractive index of the material of the prism is \( \mu \), then the angle of incidence is nearly equal to:
Read answer →Physics · PYQ NEET UG 2019(2)
The main scale of a vernier callipers has \( n \) divisions/cm. \( n \) divisions of the vernier scale coincide with \( (n - 1) \) divisions of main scale. The least count of the vernier callipers is,
Read answer →Physics · MOTION IN A STRAIGHT LINE
A body starting from rest moves along a straight line with uniform acceleration. It covers a distance \( x_1 \) in the first \( t \) seconds and an additional distance \( x_2 \) in the next \( t \) seconds. The relation between \( x_1 \) and \( x_2 \) is:
Read answer →Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
