Question

What is the work to be done to increase
the velocity of a bike from 40 km
per hour to 80 km per hour Y the most
of
the bike is 150 kg.​

Answer 1

Answer:

acceleration needs to be done

Explanation:

becoz then only the velocity will increase

Answer 2

Answer:

The work to be done to increase  the velocity of a bike having a mass 150 kg from 40 km  per hour to 80 km per hour ​ is 27777.7222 J

Explanation:

Given,

The total mass (m)   =  150 kg

Initial speed  $\left(V_{i}\right)$      =  40 km/hr = $40 \times\frac{5}{18} =\ 11.1111 \ m/s$

Final speed  $\left(V_{f }\right)$      =  80 km/hr =  $80 \times\frac{5}{18} =\ 22.2222 \ m/s$

According to the work-energy theorem,

Work done  =  Change in kinetic energy

so we have to find out the change in K.E  to obtain work done.

We have the expression for Kinetic energy (K.E) as,

$\mathrm{K} . \mathrm{E}=\frac{1}{2} m V^{2}$

So the change in K.E will be,

$\Delta \mathrm{KE}=\frac{1}{2} \mathrm{~m}\left(\mathrm{~V}_{\mathrm{f}}^{2}-\mathrm{V}_{\mathrm{i}}^{2}\right)$

          =  $\frac{1}{2} \times 150 \times\left(\left\\22.2222^{2}-\left\\11.1111^{2}\right)$

          = 27777.7222 J

       

Ans:

The Work done   = 27777.7222 J