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1) Two cars accelerate from rest to 20 m/s, both in the same direction, but in d

ID: 1272690 • Letter: 1

Question

1) Two cars accelerate from rest to 20 m/s, both in the same direction, but in different amounts of time. Which car had a greater acceleration?

More information is needed.

The car that took the least time to reach 20 m/s.

Both cars had the same acceleration.

The car that took the most time to reach 20 m/s.

2) Expressed to the correct number of significant figures, 35.2 cm+ 1.473 cm+ 6 cm=

43 42.7 42.67 42.673

3) A project of mass m moves with a speed v. What are the SI base units of the quantity KE=0.5 mv^2?

kg m^2/s^2 kg^2 m^2/s^2 kg m/s kg m^2/s

4) The velocity vs. time graph for the motion of a car on a straight track is shown in the diagram below. The thick line represents the velocity. Assume that the car starts at the origin x=0. At which time is the car greatest distance from the original? t=10s t=6s t= 5s t=3s t=0s

5) A projectile is launched across afield. As the projectile rises towards its highest point, the angle between its acceleration vector a and the horizontal   

increase

decrease

remains constant at a value of 90 degree

remains constant at some value other than 90 degree

6) A projectile is launched with a speed v0=35 m/s at some angle above the horizontal. On impacts, its speed is v=22 m/s we can conclude that

it landed at a higher elevation

it landed at a lower elevation

it landed at the same elevation

more information needed

Explanation / Answer

1-

The car that took the least time to reach 20 m/s.

2-42.673

3-kg m/s

4- t=10s

5-

decrease

6-

it landed at the same elevation