Question

A stone of mass 200 gm acquire a velocity of 2 cm/s . Its kinetic energy is *

please tell ​

Answer 1

ANSWER:

• The kinetic energy of the stone = 4 × 10⁻⁶ J.

GIVEN:

• A stone of mass 200 g acquire a velocity of 2 cm/s.

TO FIND:

• The kinetic energy of the stone.

CONVERSIONS:

• 1 kg = 1000 g

• 1 g = 10⁻³ kg

• 200 g = 200 × 10⁻³ kg

• 1 m/s = 100 cm/s

• 1 cm/s = 10⁻² m/s

• 2 cm/s = 2 × 10⁻² m/s

EXPLANATION:

KINETIC ENERGY:

• The energy possessed by a body by virtue of its motion is called Kinetic Energy.

$\boxed{\bold{\large{\red{K.E = \dfrac{1}{2} mv^2}}}}$

$\sf \leadsto K.E = \dfrac{1}{2} \times 20 \times {10}^{ - 3} \times (2 \times {10}^{ - 2} )^2$

$\sf \leadsto K.E = 10 \times {10}^{ - 3} \times 4 \times {10}^{ - 4}$

$\sf \leadsto K.E = {10}^{ - 2} \times 4 \times {10}^{ - 4}$

$\sf \leadsto K.E = 4 \times {10}^{ - 6} \ J$

Hence the kinetic energy of the stone = 4 × 10⁻⁶ J.

EXTRA INFORMATION:

POTENTIAL ENERGY:

• The energy possessed by a body by virtue of its rest is called Potential Energy.

$\boxed{\bold{\large{\blue{P.E = mgh}}}}$