You are driving down a straight highway at 20 m/s (72 km/h) on a foggy night. Suddenly you see a truck stopped directly in front of you a distance d down the roadway.
(b) What is the shortest distance d that will allow you to stop before hitting the truck?

Area of the rectangle between 0 s and 1 s is (20 m/s)×1 s = 20 m.
Area triangle is (1/2)×(20 m/s)×5 s = 50 m.
Total distance = 20 m + 50 m = 70 m.

Go on to part (c)

Part (c)
(c) Suppose the truck is only 52 m away when you first see it. What will your speed be when you collide?

What to do

Shade the area representing 52 m total displacement. Find the time at 52 m. Find the velocity at that time.

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