Amotorist driving at 25 meters/second decelerates to
15 meters/second. the combined mass of the vehicle and the driver is 1.5 × 10³ kilograms. what is the amount of mechanical work done by the vehicle?
a) 7.5 x 10^4 joules
b) 1.5 x 10^5 joules
c) 3.0 x 10^5 joules
d) 6.2 x 10^5 joules

Work done = 0.5*m*[(v2)^2 - (v1)^2]
where m is mass,
v2 and v1 are the velocities.

Given that m = 1.50 x 10^3 kg, v2 = -15 m/s (decelerates), v1 = 25 kg,

Work done = 0.5 * 1.50 x 10^3 * ((-15)^2 - 25^2) = 3 x 10^5 joules

Just ignore the negative value for the final result because work is a scalar quantity.

The purpose of a lab is to do your "expirements" the importance of the topic is so you can now what the story is about and the last one is because no one is me with my question ( what is 3 over 4 x - 9 = 27 maybe you can )