Question

Calculate the work required to be done to stop a car of 500 kg moving at a velocity of 30 km/h?
PLS HELP ME WITH THE ANSWER

Answer 1

52083.34 J

Explanation:

Given:

Mass of Car (m) = 500 kg

Velocity of Car (v) = 30 km/h

$\sf30 \: \: km/sec = 30 \times \dfrac{5}{18} \: \: m/sec = \dfrac{25}{3} \: \: m/sec$

To find:

Work required to be done to stop the car

Solution:

As We know that Work done by stopping a body is equal to the it's Kinetic Energy

$\text{Formula of Kinetic Energy(K.E)}=\sf\:\dfrac{1}{2}mass.(velocity)²$

Now,

$\frac{1}{2} \times 500 \times {(\frac{25}{3})}^{2} \\ \\ = 250 \times\frac{625}{9} \\ \\ = 52083.34$

So, The Total Work done is 52083.34 J

Answer 2

Answer:

Given :-

• A car of 500 kg moving at a velocity of 30 km/h.

To Find :-

• What is the work required to be done to stop a car.

Formula Used :-

$\boxed{\bold{\large{K.E\: =\: \dfrac{1}{2} m{v}^{2}}}}$

where,

• K.E = Kinetic energy
• m = Mass
• v = Velocity

Solution :-

Given :

• Mass = 500 kg
• Velocity = 30 km/h = $\dfrac{25}{3}$ m/sec

According to the question by using the formula we get,

⇒ K.E = $\dfrac{1}{2} \times 500 \times (\dfrac{25}{3})^{2}$

⇒ K.E = $\dfrac{1}{2} \times 500 \times \dfrac{625}{9}$

⇒ K.E = $250 \times \dfrac{625}{9}$

⇒ K.E = $\dfrac{156250}{9}$

➠ K.E = 17361.11 J

$\therefore$ The work required to be done to stop a car is 17361.11J .