Question

a body of mass 2 kg is thrown up with a velocity of 30 metre per second find the potential energy of the body at the highest point.​

Answer 1

Answer:

mass = 2kg = 2000g

g(gravity) =9.8m/s

height = 30m/s

potential energy = mgh

= 2000×9.8×30

= 60000 × 9.8

= 588000

I am not sure about this answer.

Answer 2

$\large\underline{\underline{\sf Given:}}$

• Mass of body (m) = 2kg

• Initial Velocity (u) = 30m/s

• Final Velocity (v) = 0m/s (At highest point )

• g = -10m/s²

$\large\underline{\underline{\sf To\:Find:}}$

• Potential Energy at highest point (PE) = ?

$\large\underline{\underline{\sf Solution:}}$

According to third equation of motion .

$\large{\boxed{\sf v^2=u^2-2gs}}$

$\large\implies{\sf 0=(30)^2-2×10×s }$

$\large\implies{\sf 0= 900-20s}$

$\large\implies{\sf s=\frac{900}{20}}$

$\large\implies{\sf s=45m}$

•°• Maximum Height at which body goes is 45m

We know that Potential Energy at highest point is :

$\large{\boxed{\sf PE=mgh }}$

$\large\implies{\sf PE=2×10×45 }$

$\large\implies{\sf PE=900J}$

$\large\underline{\underline{\sf Answer:}}$

•°•Potential Energy at the highest point is 900J