Question

. What is the work done to increase the velocity of a car from 36 km/h to 54 km/h, if mass of ca is 1500 kg?

Answer 1

Answer:-

initial velocity =36x5/18

u=2x5=10m/s

final velocity =54x5/18

v=3x5=15m/s

work done = change in kinetic energy

1/2mv2 - 1/2mu2

1/2x 1500x(15)2 - 1/2x1500x(10)2

750x225 - 750x100

168750-75000

93750Joules

Answer 2

Answer:

The work done to increase the velocity of a car from 36 km/h to 54 km/h if the mass of ca is 1500 kg is 93750 J.

Explanation:

Given,

Mass of the car (m) = 1500 kg

Initial velocity of the car (u) = 36 km/hr = $36\times\frac{5}{18}$ = 10 m/s

Final velocity (v)        = 54 km/hr =  $54\times\frac{5}{18}$ = 15 m/s

According to work - energy theorem,

Work done = change in kinetic energy

We have,

Kinetic energy (K.E) = $\frac{1}{2} \times m V^{2}$

Change in kinetic energy can be written as,

Δ K.E  = $\frac{1}{2}\times m(v^{2} - u^{2} )$

          = $\frac{1}{2}\times 1500\times(15^{2} - 10^{2} )$

          = 93750 J

Ans :

Work done to increase the velocity  = 93750 J