1. A 1.2 x 10^4 kg truck is travelling south at 22 m/s.(adsbygoogle = window.adsbygoogle || []).push({});

a) What net force is required to bring the truck to a stop in 330 m?

b) What is the cause of this net force?

Answer: a) 8.0 x 10^3 N [N]

2. Each of the four wheels of a car pushes on the road with a force of 4.0 x 10^3 N [down]. The driving force on the car is 8.0 x 10^3 N [W]. The frictional resistance on the car is 6.0 x 10^3 N [E]. Calculate the following:

a) the mass of the car

b) the car's acceleration

Answer: a) 1.6 x 10^3 kg b) 1.2 m/s^2 [W]

I have the answers to these two questions, but I really need help on how to understand and do it.

So far...

1. a) v = d/t

t = d/v

t = (0.33 km)/(22 m/s )

t = 0.015 s

a = v/t

a = (22 m/s )/(0.015 s)

a = 1466.7 m/s^2 ?? <====== stopped here because this makes no sense..

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# Homework Help: Net Force Questions

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