Question

An Object is placed at a certain height from ground has potentiel energy 4500 J . The height through which it's falls when it losses 40% of its posential energy ls (Mass of the object = 15Kg)​

Answer 1

Given :

Potential Energy = 4500 J

To Find :

The height through which it falls when it loses 40% of its potential energy

Solution :

Potential Energy = 4500 J

40% of potential energy = $\frac{40}{100}$ × 4500

                                        = 1800 J

Potential Energy = mgh

( where m= mass; g = acceleration due to gravity; h = height)

or,     1800       =  15 × 10 × h

∴          h           = 12 m.

∴ Height through which it falls when it loses 40% of its potential energy is 12m.

Answer 2

Given:

Mass of the object $=15kg$

Potential energy $= 4500 J$

To find:

The height from which the ball drops to lose 40% of its energy.

Solution:

• The energy possessed by an object by virtue of its position is called its potential energy.

• The potential energy is directly proportional to the position as height or length of stretching or expanding by the object.

It is given that the ball loses 40% of its energy on falling from a height (let's say "h" ).

Hence, the energy is

$E=\frac{40}{100}* 4500$    $;$ $or$

$E =1800J$

We know,

Potential energy of any object is given by $"mgh"$

Hence,

The height from which after throwing the ball, it looses 1800 J of energy is

$mgh=1800$

Substituting the given values, we get

$(15)(9.8)h = 1800$  $;$ $or$

$h = 12.2m$

Final answer:

Hence, after falling from 12.2 m, the ball loses 1800 J of energy.