Question

A stone is thrown upwards with a velocity of 30 m/s. (a) At what height will its kinetic energy be half of its potential energy? (b) Calculate the potential energy of the body if it’s mass = 5 kg.

Answer 1

Answer:

Given,

v= 30m/s,

We know that, Potential energy= mgh ....... 1

                        Kinetic Energy=1/2mv² ........ 2

  Here, Kinetic energy=1/2* Potential energy

           ⇒1/2mv²=1/2*mgh

           ⇒mv²=mgh           (Here 'm' is the mass)

           ⇒v²=gh

           ⇒(30)²=10h          ( Value of 'g'=10 m/s²)

           ⇒900=10h

           ⇒900/10=h

           ⇒90m =h

∴ The height at which the kinetic energy will be half of its potential energy is 90m .

Answer 2

Answer:

22.5 m will be height of it