. a positive charge always moves from a higher potential to a lower potential is right answer.
The speed of light : 299 792 458 m / s
Your position at time
, relative to the stop line:

The Porsche's position:

a. You pass the Porsche immediately after the time it takes for
:

at which point you both will have traveled 7.8 m from the stop line.
b. The equation in part (a) has two solutions. The Porsche passes you at the second solution of about
, at which point you both will have traveled 29 m.
c. At time
, the Porsche is moving at velocity

so that at the moment it passes you, its speed is 13 m/s, which is about 46.8 km/h and below the speed limit, so neither of you will be pulled over.
Answer:
391.67Hz
Explanation:
The fundamental frequency formula in string is expressed as;
Fo = V/2L
V is the velocity of the wave = 329m/s
L is the length of the string = 42cm = 0.42m
Substitute
Fo = 329/2(0.42)
Fo = 329/0.84
Fo = 391.67Hertz
Hence the fundamental frequency of a mandolin string is 391.67Hz
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