The earth's magnetic field is associated with the <span>core.</span>

Frequency, f, is how many cycles of an oscillation occur per second and is measured in cycles per second or hertz (Hz). The period of a wave, T, is the amount of time it takes a wave to vibrate one full cycle. These two terms are inversely proportional to each other: f = 1/T and T = 1/f.

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Answer:
a) 0.3965 j
b) 0.3112 m
Explanation:
The picture attached explains it all. Thank you
Answer:
Explanation:
Call the bike on the right A
Call the bike on the left B
The car begins it's time when it passes A
4 minutes later, it passes B.
But B has moved in 4 minutes and that is the key to the problem.
How far has B moved.
t = 4 minutes = 4/60 hours = 1/15 of an hour.
d = ?
rate = 30 km / hr
d = r * t
d = 30 km/hr * 1/15 hours = 2 km
The distance between the bikes is 5 km.
So the car has traveled 5 - 2 = 3 km
d = 3 km
r = ?
t = 4 minutes = 1/15 hour
r = d/t = 3/(1/15)= 3 / 0.066666666 = 45 km/hr.