NEET UG Work and Energy — practice questions
120 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice NEET UG Work and Energy in the app →A passenger standing in a bus is thrown backward when the bus suddenly starts moving forward. This is best expOne newton is defined as the force that gives a mass of 1 kg an acceleration of:The linear momentum of a body is defined as the product of its:The impulse of a force has the same dimensions as:The action and reaction forces of Newton's third law:For a given pair of surfaces, the coefficient of kinetic friction is usually:A constant force of 20 N acts on a 5 kg body initially at rest. Its speed after 3 s is:A 0.15 kg ball moving at 12 m s⁻¹ is hit straight back along its path with the same speed. The magnitude of thA 0.04 kg bullet moving at 90 m s⁻¹ is stopped after penetrating 0.6 m into a block. The average resistive forA box rests on the floor of a truck with coefficient of static friction 0.15. The maximum acceleration of the A block just begins to slide down an incline when the angle of inclination is 30°. The coefficient of static fA 0.02 kg bullet is fired with a speed of 300 m s⁻¹ from a 4 kg gun. The recoil speed of the gun is:A 50 kg person stands on a weighing scale inside a lift accelerating upward at 2 m s⁻² (g = 10 m s⁻²). The scaA 0.5 kg stone tied to a string is whirled in a horizontal circle of radius 2 m at a speed of 4 m s⁻¹. The tenThe maximum speed at which a car can round an unbanked circular turn of radius 150 m without skidding is (μs =A 3 kg block hangs from a light string passing over a frictionless pulley and pulls a 20 kg trolley along a hoFor a 3 kg block connected over a frictionless pulley to a 20 kg trolley (μk = 0.04, g = 10 m s⁻²), the tensioA 6 kg mass hangs from a light rope. A horizontal force of 50 N is applied at the rope's midpoint (g = 10 m s⁻One ball strikes a wall normally and rebounds with unchanged speed; an identical ball strikes at 30° to the noA net force F = 6t newton (t in seconds) acts on a 2 kg body initially at rest. The speed of the body at t = 4A block slides down a rough incline of 30° with coefficient of kinetic friction 0.2 (g = 10 m s⁻²). Its acceleA lift descends with a downward acceleration equal to g. The apparent weight of a passenger standing inside isA 10 N horizontal force is applied to a 2 kg block that pushes a 3 kg block in contact with it on a frictionleA 0.2 kg ball strikes the floor vertically at 10 m s⁻¹ and rebounds at 8 m s⁻¹. The magnitude of the impulse iThe optimum (design) speed for a car on a frictionless road banked at 45° along a curve of radius 100 m is (g Per NCERT §4.2, Aristotle's fallacy held that a force is required for which condition?Per NCERT §4.3 (Galileo's double-incline experiment), a ball released on a frictionless incline rises on the oPer NCERT §4.3, INERTIA of a body is best described as which property?Per NCERT §4.4, Newton's FIRST law states which of the following?Per NCERT §4.4, the QUANTITATIVE measure of inertia of a body is which physical quantity?Per NCERT §4.5 (definition of momentum), the momentum p of a body of mass m moving with velocity v is which?Per NCERT §4.5, momentum p is a vector with direction along which vector?Per NCERT §4.5, why is a SHORTER stopping time more painful when catching a cricket ball?Per NCERT §4.4, when a stationary bus suddenly starts, passengers are jerked backward primarily because of whiPer NCERT §4.3 (frictionless horizontal surface), a body moving on it must do which?Per NCERT §4.4 (terrestrial bodies), when an object on Earth is at rest, the gravitational force on it is balaPer NCERT §4.4, the SI unit of momentum is which?Per NCERT §4.5 (Summary 4), Newton's SECOND law in SI units states which relation?Per NCERT §4.5, the SI unit of force is the newton, with one newton equal to which value?Per NCERT §4.5 (Impulse), the IMPULSE J of a force F acting for time Δt equals which quantity?Per NCERT §4.5, an IMPULSIVE FORCE is best described by which feature?Per NCERT Example 4.4, a 0.15 kg cricket ball at 12 m/s is hit back at 12 m/s along the same line. The impulsePer NCERT §4.5, a constant force applied for the SAME time to two bodies of different masses (initially at resPer NCERT §4.5, the dimensions of FORCE are which set?Per NCERT §4.5, the second law F = m a is valid in which kind of reference frame?Per NCERT §4.5, for a body of constant mass, the second law reduces to which form?Per NCERT §4.5, the impulse-momentum theorem states that the impulse on a body equals which quantity?Per NCERT §4.5, the dimensions of IMPULSE are the same as those of which quantity?Per NCERT §4.5, the SI unit of IMPULSE is which?Per NCERT §4.6, Newton's THIRD law states that action and reaction forces are which?Per NCERT §4.6, two forces on the SAME body that happen to be equal and opposite (e.g. gravity vs normal forcePer NCERT §4.6 example, the third-law REACTION to Earth pulling a stone downward (with force mg) is which forcPer NCERT §4.7, the total momentum of an ISOLATED system (no external force) is which?Per NCERT §4.7, conservation of momentum applies in which kind of collisions between two bodies?Per NCERT §4.7, in a recoil scenario (a bullet of mass m fired at v from a rifle of mass M, initially at rest)Per NCERT Example 4.5, when a billiard ball strikes the wall normally at speed u and reflects at speed u, the Per NCERT §4.6, the force of attraction on a stone by Earth and the force of attraction on Earth by the stone Per NCERT §4.6, when you push a wall, the wall pushes back with which force?Per NCERT §4.8 (equilibrium of a particle), the necessary condition for a particle to be in EQUILIBRIUM is whiPer NCERT §4.7 (Summary), the SI unit of force from Newton's second law is which?Per NCERT §4.6 (action and reaction labelling), which statement about the labels is true?Per NCERT §4.9.1, the maximum STATIC friction force on a block on a horizontal surface obeys which inequality?Per NCERT §4.9.1, KINETIC (sliding) friction is approximately given by which relation?Per NCERT §4.9.1, the coefficients of static and kinetic friction satisfy which order?Per NCERT Example 4.7, the MAXIMUM acceleration of a train such that a box on its floor (μ_s = 0.15) remains sPer NCERT Example 4.8 (inclined plane), if a mass just starts to slide at angle θ = 15°, the coefficient of stPer NCERT §4.9.1 (rolling friction note), among rolling, sliding (kinetic), and static friction, which is typiPer NCERT §4.10 eqn 4.16, the CENTRIPETAL force needed for a body of mass m moving at speed v in a circle of rPer NCERT §4.10 eqn 4.18, the maximum speed of a car on a LEVEL circular road of radius R is which?Per NCERT §4.10 eqn 4.22, the OPTIMUM speed (no friction needed) on a banked road of angle θ is which?Per NCERT §4.10 eqn 4.21, the MAXIMUM speed on a banked road (with friction μ_s) is which expression?Per NCERT Example 4.10, a cyclist taking a R=3 m turn at 18 km/h (μ_s = 0.1) is in which condition?Per NCERT Example 4.11, a R=300 m banked-at-15° racetrack with μ = 0.2 has optimum speed approximately which vPer NCERT §5.1.1 (scalar product), A · B equals which expression?Per NCERT §5.1.1, the dot product of two PERPENDICULAR vectors is which value?Per NCERT §5.1.1, î · î (dot product of a unit vector with itself) equals which value?Per NCERT §5.3, the WORK done by a constant force F on an object undergoing displacement d is which?Per NCERT §5.3, work done by a force perpendicular to the displacement (e.g. centripetal force in UCM) is whicPer NCERT §5.3 + Points 2, work done by FRICTION (or viscous force) on a moving body is which?Per NCERT §5.4, the KINETIC energy of a body of mass m moving with speed v is which?Per NCERT §5.2, the WORK-ENERGY theorem states that net work done equals which quantity?Per NCERT §5.4, the kinetic energy is which kind of quantity?Per NCERT Example 5.4, a bullet of mass 50 g at 200 m/s emerges from plywood with 10% of initial KE. The emergPer NCERT §5.4, the dimensions of kinetic energy (and of work) are which?Per NCERT §5.1.1 (Summary 7), the scalar product is which property algebraically?Per NCERT §5.5, the work done by a VARIABLE force F(x) over displacement from x_i to x_f is which?Per NCERT §5.7, the GRAVITATIONAL potential energy of a mass m at height h above the ground (g constant) is whPer NCERT §5.7 / 5.8, a force is CONSERVATIVE if work done over a closed path equals which value?Per NCERT §5.8 eqn 5.9, a conservative force F(x) is related to its potential V(x) by which relation?Per NCERT §5.8, the principle of CONSERVATION OF MECHANICAL ENERGY holds when which condition is satisfied?Per NCERT §5.8 example, a ball dropped from height h has speed at the ground equal to which value?Per NCERT §5.8 (smooth inclined plane), an object released from rest at height h on a frictionless incline reaPer NCERT §5.8 (Points 8), is there an associated POTENTIAL ENERGY for FRICTION?Per NCERT §5.7 (Points 7), the zero of GRAVITATIONAL potential energy is conventionally chosen at which level?Per NCERT §5.7, the dimensions of POTENTIAL energy are the same as those of which quantity?Per NCERT §5.8, an object dropped from height h, just before hitting the ground, has kinetic energy equal to wPer NCERT §5.8 (conservation form), the total mechanical energy E in a conservative system is which sum?Per NCERT §5.9 eqn 5.16, Hooke's law for an ideal spring states the spring force F_s is which?Per NCERT §5.9, the SI unit of the spring constant k is which?Per NCERT §5.9 (Summary 6), the elastic potential energy stored in a spring extended by x is which?Per NCERT §5.9 Fig 5.8, in a spring-mass system at maximum extension (x = ±x_max), the kinetic energy of the bPer NCERT §5.9 Fig 5.8, at the equilibrium position (x = 0) of a spring-mass system, the kinetic energy is whiPer NCERT §5.9 example (5.8), a 1000 kg car at 18.0 km/h (= 5 m/s) hits a spring with k = 5.25×10³ N/m. MaximuPer NCERT §5.10, AVERAGE power is defined as which ratio?Per NCERT §5.10, INSTANTANEOUS power is given by which expression in terms of F and v?Per NCERT §5.10, 1 horsepower (hp) is approximately equal to which value?Per NCERT §5.10, the unit kilowatt-hour (kWh) measures which physical quantity?Per NCERT Example 5.10, a 1800 kg elevator going up at 2 m/s against 4000 N friction needs minimum motor powerPer NCERT §5.10 + Summary, the dimensions of POWER are which?Per NCERT §5.11.1, an ELASTIC collision conserves which two quantities?Per NCERT §5.11.1, in an INELASTIC collision, which quantity is conserved (and which is not)?Per NCERT §5.11.2 eqn 5.22, in a COMPLETELY inelastic 1D collision (mass m₁ at v₁ hits m₂ at rest), the commonPer NCERT §5.11.2, the KINETIC energy LOST in a completely inelastic 1D collision (m₁ at v₁ hitting m₂ at restPer NCERT §5.11.2 eqn 5.26 / 5.27, in an ELASTIC 1D collision of m₁ (v₁) with m₂ (at rest), the final velocityPer NCERT §5.11.2 Case I, in an elastic 1D collision between EQUAL masses (one at rest), the result is which?Per NCERT §5.11.2 Case II, in an elastic 1D collision where a LIGHT mass hits a much HEAVIER stationary mass (Per NCERT Example 5.11, in an elastic collision between a neutron and DEUTERIUM (m₂ = 2 m₁), the fraction of nPer NCERT Example 5.12 (2D elastic between EQUAL masses, one at rest), the two final velocities make which angPer NCERT §5.11.1, two cars colliding and locking together (no rebound) is an example of which collision type?Per NCERT §5.11 (Points 9), during the collision interval itself, conservation of momentum holds at which mome