Question

A stone of mass 100g is thrown upwards with a velocity 30m/s. What is the maximum
potential energy that can be gained by the stone?
(a) 45000J (b) 45J (c) 0J (d) 300J​

Answer 1

Answer:

A stone of mass 500g is thrown vertically upwards with a velocity of 15ms

−1

. Calculate the potential energy at the greatest height.

Medium

Answer

Kinetic Energy, K.E=0.5×m×v

2

K.E=0.5×0.5×15×15=56.25J

As it has 56.25 J at the initial point as total energy, at some point X,Potential Energy(P.E.) is maximum.

Total energy=P.E.+K.E.

56.25=P.E.+K.E.

As energy is conserved total energy at point X also must be 40 J.

For P.E to be maximum K.E. must be zero.

Hence P.E.=56.25J

We can come to the conclusion that potential energy will have the maximum value at maximum height.

Step-by-step explanation:

please mark me as a brainlist

Answer 2

$\huge\pink{\boxed{\sf Answer}}$

Gɪᴠᴇɴ :

Mass of a stone 100 g

$\begin{gathered}\longmapsto\:\bf{Mass\:(m)\:=\:100\:g\:=\:0.1\:kg} \\ \end{gathered}$

• The stone is thrown upwards with a velocity of 30m/s

$\begin{gathered}\longmapsto\:\bf{Velocity\:(v)\:=\:30\:m/s} \\ \end{gathered}$

Tᴏ Fɪɴᴅ :

The maximum potential energy gained by the stone.

Cᴀʟᴄᴜʟᴀᴛɪᴏɴ :

We know that,

✯ When body reaches the highest point, it's entire kinetic energy gets converted into potential energy, which is maximum.

Thus,

↝ Kinetic energy of a body is,

$\begin{gathered}\red\bigstar\:\:{\underline{\orange{\boxed{\bf{\purple{Kinetic\:energy\:=\:\dfrac{1}{2}\:{m}\:{v^2}\:}}}}}} \\ \end{gathered}$

$\begin{gathered}\bf{Kinetic\:energy\:=\:\dfrac{1}{2}\times{0.1}\times{(30)^2}\:} \\ \end{gathered}$

$\begin{gathered}\bf{Kinetic\:energy\:=\:\dfrac{1}{2}\times{0.1}\times{900}\:} \\ \end{gathered}$

$\begin{gathered}\bf{Kinetic\:energy\:=\:\dfrac{1}{2}\times{90}\:} \\ \end{gathered}$

$\begin{gathered}\bf\red{Kinetic\:energy\:=\:45\:Joules} \\ \end{gathered}$

Hence,

★ Here the maximum kinetic energy, i.e. 45 J is converted into potential energy (maximum).

$\begin{gathered}\bf\pink{P.E_{(max^m)}\:=\:45\:Joules} \\ \end{gathered}$

[NOTE : Potential energy is maximum at highest point.]

$\Large\tt{Therefore,}$

The maximum potential energy gain by the stone is 45 J