A distressed car is rolling backward, downhill at 3.0 m/s when its driver finally manages to

Physics

1 answer:

konstantin123 [22]3 years ago

5 0

Answer:

Explanation:

Acceleration is equal to the change in velocity over the change in time, or

$a=\frac{v_f-v_i}{t}$ where the change in velocity is final velocity minus initial velocity. Filling in:

$3.0=\frac{v_f-(-3.0)}{6.0}$ Note that I made the backward velocity negative so the forward velocity in our answer will be positive.

Simplifying that gives us:

$3.0=\frac{v_f+3.0}{6.0}$ and then isolating the final velocity, our unknown:

3.0(6.0) = v + 3.0 and

3.0(6.0) - 3.0 = v and

18 - 3.0 = v so

15 m/s = v and because this answer is positive, that means that the car is no longer rolling backwards (which was negative) but is now moving forward.

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Vector A has a magnitude of 8.0 m and points east, vector B has a magnitude of 6.0 m and points north and vector C has a magnitu

sineoko [7]

Answer:

The answer is E) 6.7m at an angle 63° north of east

Explanation:

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3 years ago

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jonny [76]

To solve this problem it is necessary to apply the concepts related to the relationship between tangential velocity and centripetal velocity, as well as the kinematic equations of angular motion. By definition we know that the direction of centripetal acceleration is perpendicular to the direction of tangential velocity, therefore:

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