Question

An engine of mass 74.6 tonnes is running with a velocity of 10m/s . Find out the additional power it must develop to increase its velocity to 15m/s in 10 minutes

Answer 1

Given :

Mass of Engine = 74.6 tone

                             1 tone = 1000 kg

                      ∴     74.6 tone = 74.6 × 1000 kg

                                               = 74600 kg

Initial velocity = 10 m/s

Final velocity = 15 m/s

Time Taken = 10 min

                      1 min = 60 sec

            ∴      10 min = 60 × 10 sec

                                = 600 sec

                                                                   

To find :

Additional power it must develop to

increase its velocity

                                                                   

So,

According to question

$F=ma\\\\F=74600\bigg(\dfrac{v-u}{t}\bigg)\\\\F=74500\bigg(\dfrac{15-10}{600}\bigg)\\\\F=74500\bigg(\dfrac{5}{600}\bigg)\\\\F=745\times\dfrac{5}{6}\\\\F=\dfrac{3725}{6}\\\\F=620.83\:N$

                                                                   

So,

we can say that it takes 620.83 N force to

increase its velocity to 15m/s in 10 minutes