Question

An object of mass 1kg has a potential energy of 1Joule relative to the ground when it is at a height of:
a) 0.102m
b) 1m
c) 9.8m
d) 32m​

Answer 1

Answer:

• The Object is at height (h) = 0.102 meters.

Given:

1. Mass of the Body (m) = 1 Kg.
2. Potential energy (E) = 1 Joule.
3. Acceleration Due to Gravity (g) = 9.8 m/s²

Explanation:

Potential Energy:-

Potential energy is the energy which a body posses due to virtue of Position.

Formula of Potential energy

P.E = Mgh

• M denotes Mass of the Body.
• g denotes Acceleration Due to Gravity.
• h Denotes the Height to which the body is raisen.

____________________________

From Potential energy Formula,

⇒ P.E = Mgh

⇒ E = M x g x h

⇒ E = 1 kg x 9.8 m/s² x h meters

⇒ E = 1 x 9.8 x h

⇒ E = 9.8 x h

∵ [ Potential Energy = 1 joule.]

Substituting,

⇒ 1 = 9.8 x h

⇒ h = 1/9.8

⇒ h = 10/98

⇒ h = 0.102 Meters.

So, The Height at which Potential Energy is 1 joule is 0.102 meters.

Note:-

• Here I took Acceleration Due to gravity(g) as 9.8 m/s².
• If you take  g = 10 m/s² , The final answer comes as 0.1 meters.

Answer 2

Answer:

Given:

Mass of object = 1 kg

Gravitational Potential Energy = 1 Joule

To find:

Height of the object

Formulas used:

Gravitational Potential Energy=

( m × g × h )

where m => mass, g => gravity and

h => height.

Concept:

We know that Gravitational Force is a conservative force. So the work done to take the object to that height is conserved / stored in the object as Potential Energy.

Calculation:

[I am considering value of g as 9.8 m/s²]

Potential Energy = 1 J

=> m × g × h = 1

=> 1 × (9.8) × h = 1

=> h = 1/(9.8)

=> h = 0.102 metres

So, the correct option is option a) 0.102 m