Start Free Mock LoginAlready registered? Login here

Physics - W.E.P. Question with Solution | TestHub

PhysicsW.E.P.Conservative force & potential energyMedium2 minQB

PhysicsMediumsingle choice

A small object with mass $m = 2 kg$ is attached to the free end of an ideal spring with $k = 10 Nm^{- 1}$ . The other end of the spring is connected to a fixed frictionless pivot located at the origin O as shown in the Figure. The relaxed length of the spring is 1 m . An unspecified force F carries the object at rest from point A to point B . At point B , the object has the speed $5 ms^{- 1}$ . The work done by the force F is (Neglect gravity) :-

Options:

Answer:

Solution:

Work-energy theorem from A to B (spring stretches from 2 m to 5 m):

$W_{F} = Δ K + Δ U = \frac{1}{2} (2) (5^{2}) + \frac{1}{2} (10) [(6 - 1)^{2} - (3 - 1)^{2}]$

$W_{F} = 25 + (125 - 20) = 130 J$

Ans. (A)

Stream:JEESubject:PhysicsTopic:W.E.P.Subtopic:Conservative force & potential energy

⏱ 2mℹ️ Source: QB

Doubts & Discussion

Loading discussions...