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Question

A 208 N force is exerted on a crate toward the north and the 182 N force is exerted toward the east. Find the magnitude and direction of the net force.
_______N
_______ degrees north of east

A street lamp weighs 200 N. It is supported by two wires that form an angle of 140° with each other. The tensions in the wires are equal.

What is the tension in each wire?
______ N
If the angle between the wires is reduced to 110°, what is the tension in each wire?
______ N

A race car has a mass of 700 kg. It starts from rest and travels 39.0 m in 3.0 s. The car is uniformly accelerated during the entire time. What net force is exerted on it?
______ N



Calculate the force you exert as you stand on the floor assuming you weigh 195 lb. (1 lb = 0.454 kg).
____N

Answer 1

1) Mag = √(208^2 + 182^2) = 276.38N

2)Each wire carries half the weight:
100/cos70 = 292.38N

3)100/cos55 = 174.34N

4)r = D/t = 39/3 = 13m/s
v(avg) = [v(zero) + v(f)]/2
2v(avg) = v(f)
v(f) = 2(13) = 26m/s
a = (v(f) - v(zero))/t
a = 26/3 = 8.6667m/s
f = ma
f = 700(8.6667)
f = 6066.7N

5) 195lb(0.454kg/lb) = 88.53kg
f = ma = mg = 88.53(9.8) = 867.594N