Question

Find the gravitational potential energy of 1 kg
mass kept at a height of 5 m above the ground.
Calculate its kinetic energy when it falls and hits the
ground. Take g = 10 m s-2. Ans. 50 J, 50 J
​

Answer 1

$\huge{ \mathtt{Given :-}}$

• Mass of the object = 1 kg
• Height above the ground = 5m
• g = 10m/s²

$\huge{ \mathtt{To \: Find :-}}$

• Gravitational Potential Energy
• Kinetic Energy

$\huge{ \mathtt{Solution:-}}$

Potential energy = mgh

= 1 × 10 × 5 = 50 Joules.

Kinetic energy = 1/2×m×v²

= 1/2 × 1 × V² => V = ?

$\huge\red{Using \: Third \: equation \: of \: motion}$

V² - U² = 2as

V² -0² = 2 (10)(5)

V² = 100

V = 10 m/s

Hence, kinetic Energy =

$= \frac{1}{2} \times 1 \times {(10)}^{2} \\ \\ = \frac{1}{2} \times 100 \\ \\ = 50 \: joules$

Hence, the kinetic energy = 50 J and potential energy = 50 J

$\huge \purple{ \underline{ \underline{ \mathtt{ \: ⭐hope \: \: this \: \: helps \: \: you⭐}}}}$