Work , Power and Energy questions with solutions

Showing 1–10 of 332 questions

• Multi-correctmediumWork , Power and EnergyPower & Its Applications

  For a particle, the instantaneous net power is $P_net.$ Which statements are correct?

  Select all that apply

  • Option A

    $P_net$ = dK/dt

  • Option B

    If $P_net$ > 0, speed is increasing at that instant

  • Option C

    If $P_net$ = 0, acceleration must be zero

  • Option D

    For uniform circular motion, net power is zero

  Check answerShow answer

  JEE MainsNEETJEE Advanced

  Open question & full solution →
• MCQdifficultWork , Power and EnergyKinetic Energy & Work-Energy Theorem

  A block of mass m is attached to a spring of force constant k along the smooth face of a freely moving wedge of mass M and angle θ. Initially the spring is unstretched and the entire system is at rest. The block is released. The maximum extension of the spring is:

  Options

  • Option A

    mg sinθ/k

  • Option B

    2mg sinθ/k

  • Option C

    2(M+m)mg sinθ/(Mk)

  • Option D

    2Mmg sinθ/[k(M+m)]

  Check answerShow answer
  Open question & full solution →
• MCQmediumWork , Power and EnergyVertical Circular Motion

  A body of m kg slides from rest along the curve of vertical circle from point A to B in friction less path. The velocity of the body at B is:

  

  (given, R = 14 m, g = 10 m/s² and √2 = 1.4)

  Options

  • Option A

    19.8 m/s

  • Option B

    21.9 m/s

  • Option C

    16.7 m/s

  • Option D

    10.6 m/s

  Check answerShow answer

  JEE Mains 2024 04 Apr Evening Shift

  Open question & full solution →
• MCQeasyWork , Power and EnergyVertical Circular Motion

  A stone is tied to a string of length 2 m is whirled in a vertical circle with the other end of the string at the centre. At a certain instant of time, the stone is at its lowest position and has a speed 10 m/s. The magnitude of the change in its velocity as it reaches a position where the string is horizontal is

  Options

  • Option A

    √60 m/s

  • Option B

    √40 m/s

  • Option C

    √80 m/s

  • Option D

    √160 m/s

  Check answerShow answer

  JEE MainsNEET

  Open question & full solution →
• IntegermediumWork , Power and EnergyKinetic Energy & Work-Energy Theorem

  A block attached to a horizontal spring is pulled to x₀ = 10 cm and released from rest on a frictionless surface. When it reaches x = 5 cm, its kinetic energy is 0.25 J. Find the spring constant k in N m⁻¹, to the nearest integer.

  Your answer

  Check answerShow answer

  JEE Mains1st Feb Evening Shit 2023

  Open question & full solution →
• Multi-correctmediumWork , Power and EnergyKinetic Energy & Work-Energy Theorem

  Which of the following statements is TRUE for a system comprising of two bodies in contact exerting frictional force on each other :

  Select all that apply

  • Option A

    total work done by static friction on whole system is always zero.

  • Option B

    work done by static friction on a body is always zero

  • Option C

    work done by kinetic friction on a body is always negative

  • Option D

    total work done by internal kinetic friction on whole system is always negative

  Check answerShow answer

  JEE Advanced

  Open question & full solution →
• NumericmediumWork , Power and EnergyPower & Its Applications

  A body of mass 1 kg begins to move under the action of a time dependent force $\overrightarrow{F}$ = (tî + 3t²ĵ) N, where î and ĵ are the unit vectors along x and y axis. The power developed by above force, at the time t = 2s. will be _______W.

  Your answer

  Check answerShow answer

  JEE Mains24 January 2023Shift 2Evening Shift

  Open question & full solution →
• MCQmediumWork , Power and EnergyConservation of Mechanical Energy

  In the figure shown the potential energy (U) of a particle is plotted against its position 'x' from origin. Then which of the following statement is correct. A particle at :

  

  Options

  • Option A

    x₁ is in stable equilibrium

  • Option B

    x₂ is in stable equilibrium

  • Option C

    x₃ is in stable equilibrium

  • Option D

    None of these

  Check answerShow answer

  JEE Mains

  Open question & full solution →
• NumericmediumWork , Power and EnergyKinetic Energy & Work-Energy Theorem

  The momentum of a body is increased by 50%. The percentage increase in the kinetic energy of the body is _________ %.

  Your answer

  Check answerShow answer

  JEE Mains8 April 2023Shift 1Morning Shift

  Open question & full solution →
• MCQmediumWork , Power and EnergyVertical Circular Motion

  A bob of mass ‘m’ is suspended by a light string of length ‘L’. It is imparted a minimum horizontal velocity at the lowest point A such that it just completes half circle reaching the top most position B. The ratio of kinetic energies (K.E.)ₐ/(K.E.)ᵦ is :

  

  Options

  • Option A

    3 : 2

  • Option B

    5 : 1

  • Option C

    2 : 5

  • Option D

    1 : 5

  Check answerShow answer

  JEE Mains 2024 29 Jan Evening Shift

  Open question & full solution →