What is the work needed to be done to increase the velocity of car from 30km / h to 60km / h if the mass of car 1500
Answers
Work = Change in kinetic energy
= 0.5 m (v² - u²)
= 0.5 × 1500 kg × [(60 × 5/18 m/s)² - (30 × 5/18 m/s)²]
= 156250 joules
= 156.25 kJ
Work done is 156.25 kJ
Answer:
Work done is 156250 J.
Explanation:
Given,
The mass (m) of the car is 1500 kg.
Initial velocity of car = u = 30 km / hr = 30 * 5/18 = 25 / 3 m/s
Final velocity of car = v = 60 km / hr = 60 * 5/18 = 50/3 m/s
To find: The work to be done to increase the velocity of a car from
30 km h-1 to 60 km h^-1
Solution:
Initial kinetic energy = Ki = 1/2mu² = 1/2*1500*25/3 * 25/3 = 156250/3 J
Final Kinetic energy = Kf = 1/2mv² = 1/2*1500*50/3*50/3 = 625000/3 J
Work done can be given as change in Kinetic Energy,
i.e W = ΔK.E
or, W = Kf - Ki
or, W = 625000/3 - 156250/3
or, W = 156250 J
Therefore, Work done is 156250 J.