Question

Hi brainly friends, 

You have a new challenge .

$\huge \fbox \orange{❥Question}$

What is the work to be done to increase the velocity of a car from 20km/h to 40km/h if the mass of the car is 2000 kg?

Correct Answers√

No Spamming.

Try to Answer! 

This is your chance to get Brainly stars rank.. 

Best of luck. 

Be Brainly™.​

Answer 1

Answer:

Here ur answer.

Given, intial velocity ,u- 20km/hr = 20×5/18=50/9 m/s

final velocity, v- 40 km/hr=40×5/18=100/9 m/s

mass, m= 2000kg

2 2

Workdone = 1×mv /2-1×mu /2

==>W=m(v2- u2) /2

=2000[100/9×100/9-50/9×50/9]/2

= 2000(10000/81 -2500/81) /2

=2000(7500/81) /2

=92,592.5J

Answer 2

$\boxed{\underbrace{\overbrace{\bf{\orange{QUESTION}}}}}$

What is the work to be done to increase the velocity of a car from 20km/h to 40km/h if the mass of the car is 2000 kg?

$\boxed{\underbrace{\overbrace{\bf{\green{ANSWER}}}}}$

$: \longrightarrow \bf{Initial\: velocity\:(u)} \:=\: 20km/h$

$\implies u \:=\: 20 \times \bf{\frac{1000}{60\:×\:60}}$

$\implies u \:=\: \bf{\frac{50}{9}}$

$: \longrightarrow \bf{Final\: velocity\:(v)} \:=\: 40km/h$

$\implies v \:=\: 40 \times \bf{\frac{1000}{60\:×\:60}}$

$\implies v \:=\: \bf{\frac{100}{9}}$

$\therefore$ Work Done , W = $\frac{1}{2} \times mv²$

$\implies W \:=\: \frac{1}{2} \times 2000 \:×\: ( v² - u² )$

$\implies W \:=\: \frac{2000}{2} \times ( (\frac{100}{9})^{2} \:-\: (\frac{50}{9})^{2} )$

$\implies W \:=\: 1000 \times \frac{10000}{81} \:-\: \frac{2500}{81}$

$\implies W \:=\: 1000 \times \frac{7500}{81}$

$\implies W \:=\: 92592.9$ ( approx )