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Physics · MOTION IN A STRAIGHT LINE
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Physics · MOTION IN A STRAIGHT LINE
A police van moving on a highway with a speed of \( 30\text{ km h}^{-1} \) fires a bullet at a thief's car speeding away in the same direction with a speed of \( 192\text{ km h}^{-1} \). If the muzzle speed of the bullet is \( 150\text{ m s}^{-1} \), with what speed does the bullet hit the thief's car?
Read answer →Physics · PYQ NEET UG 2019(1)
An electron is accelerated through a potential difference of \( 10,000\text{ V} \). Its de Broglie wavelength is, (nearly) (\( m_e = 9 \times 10^{-31}\text{ kg} \))
Read answer →Physics · PYQ NEET UG 2019(1)
Increase in temperature of a gas filled in a container would lead to:
Read answer →Physics · LAWS OF MOTION
Given below are two statements: Statement I: The law of conservation of linear momentum is a direct fundamental consequence of Newton's second and third laws of motion applied to an isolated system. Statement II: In an inelastic collision between two colliding bodies, the total kinetic energy of the system is conserved, but the total linear momentum is not conserved. In the light of the above statements, choose the most appropriate answer from the options given below:
Read answer →Physics · PYQ NEET UG 2019(1)
Two point charges A and B, having charges \( +Q \) and \( -Q \) respectively, are placed at certain distance apart and force acting between them is \( F \). If \( 25\% \) charge of A is transferred to B, then force between the charges becomes:
Read answer →Physics · MOTION IN A PLANE
A motorboat is racing towards north at \( 25\text{ km/h} \) and the water current in that region is \( 10\text{ km/h} \) in the direction of \( 60^\circ \) east of south as shown in the vector diagram. The direction angle \( \phi \) of the resultant velocity vector relative to the north direction is approximately:
Read answer →Physics · Electrostatic Potential
Inside a uniformly polarised dielectric slab, the net charge in any macroscopic volume element \( \Delta v \) is zero because:
Read answer →Physics · PYQ NEET UG 2018
A sample of \( 0.1\text{ g} \) of water at \( 100^\circ\text{ C} \) and normal pressure (\( 1.013 \times 10^5\text{ Nm}^{-2} \)) requires \( 54\text{ cal} \) of heat energy to convert to steam at \( 100^\circ\text{ C} \). If the volume of the steam produced is \( 167.1\text{ cc} \), the change in internal energy of the sample, is
Read answer →Physics · PYQ NEET UG 2023
The radius of inner most orbit of hydrogen atom is \( 5.3 \times 10^{-11}\text{ m} \). What is the radius of third allowed orbit of hydrogen atom?
Read answer →Physics · LAWS OF MOTION
In the given diagram, a girl whirls a stone tied to a string in a horizontal circle at a constant speed \( v \). If the string breaks suddenly at the point shown, what will be the immediate trajectory of the stone relative to the ground, viewed from directly above?
Read answer →Physics · PYQ NEET UG 2024
A force defined by \( F = \alpha t^2 + \beta t \) acts on a particle at a given time \( t \). The factor which is dimensionless, if \( \alpha \) and \( \beta \) are constants, is:
Read answer →Physics · PYQ NEET UG 2021
The half-life of a radioactive nuclide is \( 100\text{ hours} \). The fraction of original activity that will remain after \( 150\text{ hours} \) would be:
Read answer →Physics · LAWS OF MOTION
Refer to the given figure showing a block of mass \( 4\text{ kg} \) on an inclined plane at angle \( \theta \). What are the components of the gravitational force \( mg \) parallel and perpendicular to the inclined plane respectively?
Read answer →Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
Given below are two statements: Statement I: The motion of the axis of a spinning top sweeping out a cone around the vertical is termed precession. Statement II: In precession of a spinning top, the point of contact of the top with the ground remains fixed. In the light of the above statements, choose the most appropriate answer from the options given below:
Read answer →Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
A projectile of mass \( 3m \) is fired from the origin with speed \( u \) at an angle of \( 45^\circ \) to the horizontal. At the highest point of its trajectory, it explodes into two fragments of mass \( m \) and \( 2m \). If the fragment of mass \( m \) immediately falls vertically downwards to the ground, at what horizontal distance from the origin does the fragment of mass \( 2m \) land? (Neglect air resistance, \( R \) is original range).
Read answer →Physics · WORK, ENERGY AND POWER
An electric pump is used to fill a water tank of capacity \( 30\text{ m}^3 \) located at a height of \( 40\text{ m} \) above the ground in \( 15\text{ minutes} \). If the overall efficiency of the pump is \( 30\% \) and \( g = 9.8\text{ m s}^{-2} \), the electrical power consumed by the pump is:
Read answer →Physics · UNITS AND MEASUREMENT
A spherical surface area element \( dA = 0.25\text{ m}^2 \) at a distance \( r = 0.5\text{ m} \) from the center subtends a solid angle \( \Omega \). An arc of length \( ds = 0.2\text{ m} \) on a circle of the same radius \( r = 0.5\text{ m} \) subtends a plane angle \( \theta \). The ratio of the numerical value of \( \Omega \) (in steradians) to \( \theta \) (in radians) is:
Read answer →Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
A rigid body rotates about a fixed axis with an angular acceleration of \( 5\text{ rad/s}^2 \). If the moment of inertia of the body about this axis is \( 12\text{ kg}\cdot\text{m}^2 \), the magnitude of the external torque acting on the body is:
Read answer →Physics · Electrostatic Potential
A conductor and a dielectric slab are placed separately in a uniform external electric field \( \mathbf{E}_0 \). If \( \mathbf{E}_{\text{in}} \) represents the induced electric field inside each material, the net electric field inside them satisfies:
Read answer →Physics · PYQ NEET UG 2021
Match List-I with List-II: List-I List-II A Drift Velocity P \( \frac{m}{ne^2\rho} \) B Electrical Resistivity Q \( nev_d \) C Relaxation Period R \( \frac{eE}{m}\tau \) D Current Density S \( \frac{E}{J} \)
Read answer →Physics · LAWS OF MOTION
A rubber ball of mass \( 0.15\text{ kg} \) is dropped from a height of \( 5\text{ m} \) onto a hard floor. It rebounds upwards to a maximum height of \( 3.2\text{ m} \). If the time of collision with the floor is \( 0.03\text{ s} \) and \( g = 10\text{ m/s}^2 \), the average normal force exerted by the floor on the ball during the impact is:
Read answer →Physics · PYQ NEET UG 2016(2)
A filament bulb (\( 500\text{W}, 100\text{V} \)) is to be used in a \( 230\text{ V} \) main supply. When a resistance is connected in series, it works perfectly and the bulb consumes \( 500\text{ W} \). The value of R is
Read answer →Physics · SYSTEMS OF PARTICLES AND ROTATIONAL MOTION
