Question

what is the work to be done to increase the velocity from 18 km/hr to 19 km/hr​

Answer 1

m=2000kg

u=18km/hr=5m/s

v=19=5.3m/s

wd=1/2mv^2-1/2mu^2

=300 j

Answer 2

Given:

Initial velocity u=18km/h=5m/s

Final velocity v=19km/h=5.278m/s

Mass of the car m=2000kg

To find:

Work done in increasing the velocity of the car from uto v.

Solution:

Let Wbe the work and ΔK=Kf−Kibe the increase in kinetic energy. (Here Kfand Kiare the final and initial kinetic energies respectively.)

From the work-energy theorem, we know that the work done will equal the change in kinetic energy. That is W=K.

Kinetic energy of a particle K=12mv2

Hence, the increase in kinetic energy can be found by subtracting the initial kinetic energy from the final kinetic energy

K=12mv2−12mu2

=> 12m(v2−u2)

= 12(2000)(5.2782−52)

= 5714.5682

= 2854.28J.

hope it will help you