Hello!
Use the formula:
W = Fd
Replacing:
W = 300 N * 300 m
Resolving:
W = 90000 J
The work is <u>90000 Joules.</u>
It's called cellular differentiation. I think.
It will be 49 Newtons of force in the down direction. To find the force in newtons, you multiply the mass (5 kg) by the gravity (which if 9.8).
They do the method 3 times to be sure. Because if you do it once, that could mean anything. If you do it twice, it may or may not have the same result. If you do it 3 times and it matches one of the previous answers, then it's likely that it's correct.
According to the Work-Energy Theorem, the work done on an object is equal to the change in the kinetic energy of the object:

Since the car ends with a kinetic energy of 0J (because it stops), then the work needed to stop the car is equal to the initial kinetic energy of the car:

Replace m=1100kg and v=112km/h. Write the speed in m/s. Remember that 1m/s = 3.6km/h:

Therefore, the answer is: 532,346 J.