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Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
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Physics · PYQ NEET UG 2022
वह ग्राफ जो किसी कण की दे ब्रॉग्ली तरंगदैर्ध्य (\( \lambda \)) और उसके संबंधित संवेग (\( \p \)) के विचरण को दर्शाता है, है:
Read answer →Physics · UNITS AND MEASUREMENT
Evaluate the sum \( 436.32 \text{ g} + 227.2 \text{ g} + 0.301 \text{ g} \) by properly considering the rules of significant figures and decimal places in addition.
Read answer →Physics · PYQ NEET UG 2018
If the mass of the Sun were ten times smaller and the universal gravitational constant were ten times larger in magnitude, which of the following is not correct?
Read answer →Physics · PYQ NEET UG 2017
Two cars moving in opposite directions approach each other with speed of \( 22\text{ m/s} \) and \( 16.5\text{ m/s} \) respectively. The driver of the first car blows a horn having a frequency \( 400\text{ Hz} \). The frequency heard by the driver of the second car is (velocity of sound \( 340\text{ m/s} \))
Read answer →Physics · UNITS AND MEASUREMENT
Velocity \( v \) of a wave on a stretched string depends on tension \( F \) and mass per unit length \( \mu \). The correct relation between \( v \), \( F \), and \( \mu \) obtained by dimensional analysis is:
Read answer →Physics · WORK, ENERGY AND POWER
Refer to the figure showing a bob of mass \( m \) suspended by a light string of length \( L \) undergoing circular motion in a vertical plane. When the bob reaches point \( B \) at the horizontal level, the magnitude of its total acceleration is:
Read answer →Physics · PYQ NEET UG 2018
A set of 'n' equal resistors, of value 'R' each, are connected in series to a battery of emf 'E' and internal resistance 'R'. The current drawn is I. Now, the 'n' resistors are connected in parallel to the same battery. Then the current drawn from battery becomes \( 10\text{ I} \). The value of 'n' is Which of the above statements is/are correct?
Read answer →Physics · WORK, ENERGY AND POWER
A raindrop falling from a great height attains terminal speed when the opposing drag force balances gravity. If a falling raindrop of mass \( 3.5\times 10^{-5}\text{ kg} \) has attained a terminal speed of \( 9.0\text{ m s}^{-1} \), its kinetic energy is closest to:
Read answer →Physics · LAWS OF MOTION
A body of mass \( m = 3\text{ kg} \) moves under the influence of a time-dependent force such that its position vector is given by \( \mathbf{r}(t) = (t^3 \hat{i} + 2t^2 \hat{j} - t \hat{k})\text{ m} \). Determine the magnitude of the net force acting on the body at \( t = 1\text{ s} \) and the magnitude of the impulse delivered to the body during the time interval from \( t = 0\text{ s} \) to \( t = 1\text{ s} \).
Read answer →Physics · PYQ NEET UG 2016(2)
If an electron in a hydrogen atom jumps from the \( 3^{\text{rd}} \) orbit to the \( 2^{\text{nd}} \) orbit, it emits a photon of wavelength \( \lambda \). When it jumps from the \( 4^{\text{th}} \) orbit to the \( 3^{\text{rd}} \) orbit, the corresponding wavelength of the photon will be
Read answer →Physics · UNITS AND MEASUREMENT
The mean length of a rod measured by Vernier callipers is to be reported. Why is a set of 100 measurements expected to yield a more reliable estimate than a set of 5 measurements?
Read answer →Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
A uniform square sheet of side \( 2a \) has a square of side \( a \) removed from one of its corners. Taking the corner of the original square that is diametrically opposite to the removed square as the origin, what is the distance of the centre of mass of the remaining portion from this origin?
Read answer →Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
Consider the following statements regarding the centre of mass (CM) and centre of gravity (CG) of an extended body: (A) The centre of mass of a body depends on the distribution of its mass and is independent of the gravitational field. (B) The centre of gravity of a body coincides with its centre of mass only if the gravitational field is uniform across all parts of the body. (C) In an extended non-uniform gravitational field, the net gravitational torque on the body about its centre of mass is necessarily zero. (D) The total torque on a system is independent of the choice of origin if the net external force on the system is zero. Choose the correct answer from the options given below:
Read answer →Physics · UNITS AND MEASUREMENT
Which of the following equations is dimensionally INCORRECT? (where \( s \) is displacement, \( u \) is initial velocity, \( a \) is acceleration, \( t \) is time, \( \lambda \) is wavelength, and \( T \) is time period)
Read answer →Physics · MOTION IN A STRAIGHT LINE
Referring to the schematic motion diagram shown in Fig. 2.6, a ball is thrown vertically upwards from point A (top of a building of height \( y_0 = 25 \text{ m} \)) with an initial speed \( v_0 = 20 \text{ m/s} \). It reaches its peak position B and then falls down to point C on the ground. Taking \( g = 10 \text{ m/s}^2 \), calculate the ratio of the time taken by the ball to travel from A to B (\( t_{AB} \)) to the time taken to travel from B to C (\( t_{BC} \)).
Read answer →Physics · WORK, ENERGY AND POWER
Given below are two statements: Statement I: The scalar product of two vectors is non-commutative, such that \( \mathbf{A}\cdot\mathbf{B} = -\mathbf{B}\cdot\mathbf{A} \). Statement II: The scalar product of two vectors does not obey the distributive law over vector addition. In the light of the above statements, choose the most appropriate answer from the options given below:
Read answer →Physics · PYQ NEET UG 2023
In a plane electromagnetic wave travelling in free space, the electric field component oscillates sinusoidally at a frequency of \( 2.0 \times 10^{10}\text{ Hz} \) and amplitude \( 48\text{ V m}^{-1} \). Then the amplitude of oscillating magnetic field is : (Speed of light in free space \( = 3 \times 10^8\text{ m s}^{-1} \))
Read answer →Physics · WORK, ENERGY AND POWER
A body of mass \( 0.5\text{ kg} \) travels along the x-axis with a velocity given by \( v(x) = a x^{3/2} \), where \( a = 5\text{ m}^{-1/2}\text{ s}^{-1} \). The work done by the net force acting on the body during its displacement from \( x = 0 \) to \( x = 2\text{ m} \) is:
Read answer →Physics · PYQ NEET UG 2025
The radius of Martian orbit around the Sun is about 4 times the radius of the orbit of Mercury. The Martian year is 687 Earth days. Then which of the following is the length of year on Mercury?
Read answer →Physics · LAWS OF MOTION
A machine gun fires bullets of mass \( 40\text{ g} \) each with a muzzle speed of \( 1200\text{ m/s} \). If the gunman can exert a maximum holding force of \( 144\text{ N} \) on the gun to prevent it from moving backward, the maximum rate at which bullets can be fired per second is:
Read answer →Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
A projectile is moving along a parabolic trajectory. In mid-air, it explodes into several fragments due to an internal explosion. Neglecting air resistance, the centre of mass of the fragments:
Read answer →Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
An ideal rigid body is defined as a system of particles in which the distances between all pairs of particles do not change under the influence of forces. Which of the following best describes the real-world validity of this model?
Read answer →Physics · PYQ NEET UG 2017
