Question

A body of mass 20 kg is raised up to a certain height due to which the
energy gained by it is 1960 J. Find out the height.​

Answer 1

Answer:

The height at which the body is 10 m.

Step-by-step explanation:

Given:

Mass of the body = 20 kg

Energy gained = 1960 J

To find:

Height

Solution :

The body is at a point above the ground level. The energy possessed by it is GRAVITATIONAL POTENTIAL ENERGY.

$\boxed{\sf{PE_g = mgh}}$

• m = 20 kg
• g = 9.8 m/s²
• h = ??

$\longrightarrow{\sf{1960 = 20 \times 9.8 \times h}}$

$\longrightarrow{\sf{1960 =196h}}$

$\longrightarrow{\sf{h = \dfrac{1960}{196}}}$

$\longrightarrow{\sf{h = 10}}$

Height = 10 m

Therefore, the height at which the body is 10 m.

Answer 2

$\Large{\underbrace{\underline{\bf{Given\::}}}}$

• Mass of a body is 20 kg.

• Energy gained by the body to raise a certain is 1960 J.

$\Large{\underbrace{\underline{\bf{To\: Find\::}}}}$

• The height upto what the body raised up.

$\Large{\underbrace{\underline{\bf{Solution\::}}}}$

✯ When an object is moved to a certain height, then some energy is gained by the object and it is called as Potential energy.

☛ To calculate height we use the relation between potential energy and height, given as

$\orange\bigstar\:\mid\:\bf\pink{P.E\:(U)\:=\:m\:g\:h\:}\:\mid\:\green\bigstar$

Where,

• g is the gravitational acceleration, i.e. 9.8 m/s².

➳ Height (h) = $\tt{\dfrac{U}{m\:g}}$

➳ Height (h) = $\tt{\dfrac{1960}{20\times{9.8}}}$

➳ Height (h) = $\tt{\dfrac{1960}{2\times{98}}}$

➳ Height (h) = $\tt{\dfrac{1960}{196}}$

➳ Height (h) = $\bf\purple{10\:m}$

∴ The height at which the body is raised up is 10 m.