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प्रश्न
The sign of work done by a force on a body is important to understand. State carefully if the following quantity is positive or negative:
Work done by the resistive force of air on a vibrating pendulum in bringing it to rest.
उत्तर
The work done by the resistive force of air on a vibrating pendulum in bringing it to rest is negative.This is because the resistive force's direction is opposite to the pendulum's motion. Thus, θ = 180°,
`W = Fdcosθ = F.dcos 180° = -Fd` (negative)
संबंधित प्रश्न
A body of mass 2 kg initially at rest moves under the action of an applied horizontal force of 7 N on a table with coefficient of kinetic friction = 0.1. Compute the
- Work done by the applied force in 10 s
- Work done by friction in 10 s
- Work done by the net force on the body in 10 s
- Change in kinetic energy of the body in 10 s and interpret your results.
A particle is released from the top of an incline of height h. Does the kinetic energy of the particle at the bottom of the incline depend on the angle of incline? Do you need any more information to answer this question in Yes or No?
Can the work by kinetic friction on an object be positive? Zero?
Can static friction do nonzero work on an object? If yes, give an example. If no, give reason.
Can normal force do nonzero work on an object? If yes, give an example. If no, give reason.
Two springs A and B(kA = 2kB) are stretched by applying forces of equal magnitudes a the four ends. If the energy stored in A is E, that in B isA
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A particle of mass 500 gm is moving in a straight line with velocity v = bx5/2. The work done by the net force during its displacement from x = 0 to x = 4 m is : (Take b = 0.25 m-3/2 s-1).
In the given figure, the block of mass m is dropped from point 'A'. The expression for the kinetic energy of the block when it reaches point 'B' is ______.
The sign of work done by a force on a body is important to understand. State carefully if the following quantity is positive or negative:
Work done by an applied force on a body moving on a rough horizontal plane with uniform velocity.
