Question

A car is travelling at a velocity of 10m/s and it has a mass of 25kg . Compute it's kinetic energy.​

Answer 1

Given :

• Velocity of car (v) = 10 m/s
• Mass of car (m) = 25 kg

To Find :

• The kinetic energy = ?

Solution :

Kinetic energy is the energy of motion, every object in motion posses some kinetic energy.

We can calculate the Kinetic energy by the given formula :

• K.E = ½ mv² .

Where,

• K.E is kinetic energy,
• m is mass of the car
• v is the velocity of the car

• By observing the formula we can state that kinetic energy is directly proportional to mass and velocity of the car.

Now,plug in the given values in above formula of Kinetic energy :

→ Kinetic energy = ½ × 25 × (10)²

→ Kinetic energy = ½ × 25 × 100

→ Kinetic energy = 25 × 50

→ Kinetic energy = 1,250 J

• Hence,the Kinetic energy of the car is 1,250 J.

Answer 2

$\small \underline \bold{For \: a \: Car}$:-

$\large \underline \bold{Given}$:-

$\: \: \: \: \: \: \: \: \:$ velocity$\:$=$\:$10 m/s

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$mass$\:$=$\:$25 Kg

$\large \underline \bold{To \: Find}$:-

• Compute the kinetic energy of the

ㅤㅤcar ?

$\large \underline \bold{Usable \: Formula}$:-

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$$\large\boxed{\sf\pink{KE \: = \: \dfrac{1}{2}m v^{2}}}$

here ,

$\: \: \: \: \: \: \: \:$KE$\:$=$\:$ kinetic energy

$\: \: \: \: \: \: \: \: \: \:$m$\:$=$\:$mass of the car

$\: \: \: \: \: \: \: \: \: \: \:$v$\:$=$\:$ velocity of the car

$\large \underline \bold{Solution}$:-

On putting the values in above formula -

$\: \: \: \: \: \: \: \: \: \: \: \:$$\sf{KE \: \: = \: \: \dfrac{1}{2}\times 25\times (10)^{2}}$

$\: \: \: \: \: \: \: \: \: \: \: \:$$\sf{KE \: \: = \: \: \dfrac{1}{\cancel{2}}\times 25\times \cancel{100} \: \: 50}$

$\: \: \: \: \: \: \: \: \: \: \: \:$$\sf{KE \: \: = \: \: 25\times 50}$

$\: \: \: \: \: \: \: \: \: \: \: \:$$\sf{KE \: \: = \: \: 25\times 25\times 2}$

$\: \: \: \: \: \: \: \: \: \: \: \:$$\sf{KE \: \: = \: \: 625\times 2}$

$\: \: \: \: \: \: \: \: \: \: \: \:$$\sf{KE \: \: = \: \: 1250 \: J}$

$\: \: \: \: \: \: \: \:$$\large \bold{KE \: = \: 1.25 \: KJ}$