units vectors and motion 1

1. Describe a situation in which average velocity is equal to instantaneous velocity?

2. Can an object with constant acceleration reverse its direction of travel? Can it reverse its

direction twice? In both cases, explain your reasoning.

3. A package falls out of an airplane that is flying in a straight line at a constant altitude and

speed. If you ignore air resistance, what would be the shape of the path of the package as

observed by the pilot? As observed by a person on the ground?

4. A baseball player hits a ball that soars high into the air. After the ball

has left the bat, and while it is traveling upward, what is the direction of acceleration? Ignore air resistance.

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1. Orange Krypton. How many wavelengths of

orange krypton-86 light would fit into the thickness

of a piece of paper?

2. Fastest Man on Earth. A world’s land speed

record was set by Colonel John P. Stapp when in

March 1954 he rode a rocket-propelled sled that

moved along a track at 1020 km/h. He and the

sled were brought to a stop in 1.4 s. In terms of g,

what acceleration did he experience while

stopping?

3. Kicking an Extra Point.  In football, after a touchdown the team has the opportunity to

earn one more point by kicking the ball over the bar between the goal posts. The bar is

3m above the ground, and the ball is kicked from ground level, 12m horizontally from the

bar. If the ball is kicked at 45.0° above the horizontal, what must its initial speed be if it

is just to clear the bar?

4. If a = (-2,3,1), b = (0,4,0), and c = (-1,3,3), then find (a × b) ⋅ c