Question

An engine having 2000kg change it's velocity to 30km/h to 45km/h find What is the work done by engine​

Answer 1

Correct question:-

An engine having mass 2000kg changes it's velocity from 30km/h to 45km/h . Find what is the work done by the engine.

Given:-

→ Mass of the engine = 2000kg

→ Initial velocity of the engine = 30km/h

→ Final velocity of the engine = 45km/h

To find:-

→ Work done by the engine.

Solution:-

Firstly, let's convert the initial and final velocity of the engine from km/h to m/s.

⇒1 km/h = 5/18 m/s

⇒30 km/h = 30×5/18

⇒8.33 m/s [Initial]

⇒45 km/h = 45×5/18

⇒12.5 m/s [Final]

_______________________________

Work done = Change in K.E.

⇒W = 1/2mv² - 1/2mu²

⇒W = 1/2m[v² - u²]

⇒W = m/2[v² - u²]

Where :-

• W is work done.

• m is mass of the body.

• v is final velocity.

• u is initial velocity.

⇒W = 2000/2[(12.5)² - (8.33)²]

⇒W = 1000[156.25 - 69.3889]

⇒W = 1000[86.8611]

⇒W = 86861.1 J

Thus, work done by the engine is 86861.1 J .