Q. 1. What do you mean by kinetic energyDerive the formula of kinetic

1.	Q. 1. What do you mean by kinetic energyDerive the formula of kinetic energy for amoving body
Answer» Kinetic energy is the energy possessed by an object by virtue of its motion.K.E=1/2 mV² Derivation:Let us consider an object of m which is at rest lying on a table.Let A force F acts on the object which moves the object through a distance S. The workdone=FxS W=Fnet XS-------(1) Let the workdone on the object causes a change in its velocity from u to V and let a be the acceleration. From Third equation of motion:V²-u²=2ass=V²-u²/2a----------(2) By Newton's Second law:F=ma------(3)From equation (1), (2) and (3) W=ma*(V²-u²/2a)\=(1/2)m(V²-u²) As we assumed object at rest, u=0W=(1/2)mV²we know that the kinetic energy of a body moving with certain velocity is equal to workdone on the object to acquire that velocity from rest.∴K.E=1/2 mV²

Q. 1. What do you mean by kinetic energyDerive the formula of kinetic energy for amoving body

Answer»

Kinetic energy is the energy possessed by an object by virtue of its motion.K.E=1/2 mV²

Derivation:Let us consider an object of m which is at rest lying on a table.Let A force F acts on the object which moves the object through a distance S.

The workdone=FxS

W=Fnet XS-------(1)

Let the workdone on the object causes a change in its velocity from u to V and let a be the acceleration.

From Third equation of motion:V²-u²=2ass=V²-u²/2a----------(2)

By Newton's Second law:F=ma------(3)From equation (1), (2) and (3)

W=ma*(V²-u²/2a)\=(1/2)m(V²-u²)

As we assumed object at rest, u=0W=(1/2)mV²we know that the kinetic energy of a body moving with certain velocity is equal to workdone on the object to acquire that velocity from rest.∴K.E=1/2 mV²

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