(1) What is the magnitude of the net force on a skydiver in N when an 810 N gravitational force and a 750N force of air resistance act on him?(adsbygoogle = window.adsbygoogle || []).push({});

Fn = 810

Fg = 750

810 - 750 = Fm

60N

(2) A 1200 kg car is moving in a staright line at a constant speed of 15m/s when the brakes are applied. The coefficeient of friction between the car and the road is 0.25. How far in m does the car travel after the brakes are applied?

Fn = 1200*9.8

F = u*Fn = 2940N

-F = m*a

a = -F/m = -2940/1200 = -2.45m/s^2

Vf^2 = Vi^2 +2a*deltaX

0 = Vi^2 +2adeltaX

-Vi^2/2a = deltaX = -15^2/-2.45 = 45.92m

4.) A car moves in a circle of 30 m radius. It moves with constant speed and makes one complete revolution in 22s. What is its speed in m/s?

A = V^2/r

that's all I have for this problem..

can you guys help me out with this?

Also, are my answers for 1 and 2 correct?

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# Homework Help: Application of Newtons' Law

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