A car and a truck are traveling in the same direction along a straight section of highway. The car is moving at 55 mph and the truck is moving 45 mph. what is the velocity of the car relative to the truck?

Question

anonymous · Answer

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when we say 45 mph, what we are really saying is, 'we are traveling 45 mph faster than the ground is (because the ground isn't moving).
so if we pretend that everything in this world is moving at 45mph, how fast is the car actually traveling?  Or, how much faster is the car moving than the truck, is another way to say it.