Answer:
amount of work done, W = 549.36 kJ
Given:
mass of a car engine, m = 2500 kg
initial velocity, u = 45 mph
final velocity, v = 65 mph
1 mile = 1609
Solution:
We know that 1 hour = 3600 s
Now, velocities in m/s are given as:
u = 45 mph = [tex]\frac{45\times 1609}{3600}[/tex] = 20.11 m/s
v = 65 mph = [tex]\frac{65\times 1609}{3600}[/tex] = 29.05 m/s
Now, the amount of work done, W is given by the change in kinetic energy of the car and is given by:
W = [tex]\frac{1}{2}m\Delta v^{2}[/tex]
W = [tex]\frac{1}{2}m\times (v^{2} - u^{2})[/tex]
W = [tex]\frac{1}{2}2500\times (29.05^{2} - 20.11^{2})[/tex]
W = 549.36 kJ
