Question

a man 50 kg mass has PE of 9800 J at certain height from the ground . find his height from ground at which his PE is reduced by 2450 j​

Answer 1

Answer:

$\sf{The \ man \ should \ be \ at \ the \ height}$

$\sf{of \ 15 \ m \ from \ the \ ground. }$

Given:

$\sf{A \ man \ of \ 50 \ kg \ mass \ has \ Potential \ energy}$

$\sf{of \ 9800 \ J \ at \ certain \ height. }$

To find:

$\sf{The \ height \ of \ man \ from \ the \ ground \ if}$

$\sf{potential \ energy \ is \ reduced \ by \ 2450 \ J}$

Calculation:

$\sf{Reduced \ potential \ energy=9800-2450}$

$\sf{Now, \ Potential \ energy=7350}$

$\boxed{\sf{Potential \ Energy=mgh}}$

$\sf{7350=50(9.8)\times \ h}$

$\sf{\therefore{h=\dfrac{735}{49}}}$

$\sf{\therefore{h=15 \ m}}$

$\sf\purple{\tt{\therefore{The \ man \ should \ be \ at \ the \ height}}}$

$\sf\purple{\tt{of \ 15 \ m \ from \ the \ ground. }}$

_____________________________________

Extra information:

$\sf{\leadsto{Density=\dfrac{Mass}{Volume}}}$

$\sf{\leadsto{Pressure=\dfrac{Force}{Area}}}$

$\sf{\leadsto{Impulse=Pressure\times \ Time}}$

$\sf{\leadsto{Frequency=\dfrac{1}{Time}}}$

Answer 2

Explanation:

Reduced potential energy 9800–2450

Now, Potential energy = 7350

Potential Energy = mgh

7350 = 50(9.8) × h

h = 735/ 49m

h=15 m

⋆The man should be at the height

of 15 m from the ground.