Answer:
I think it is
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Given data:
● Angular velocity of the turntable ω = 33 rev/min
Therefore,
ω = 33 rev/min
ω = 33rev/min × 2π rad/rev × 1 min/60 sec = 3.45 rad/s
● The distance of the watermelon seed from the axis of rotation r = 7.8 cm = 0.078 m
● μs = the coefficient of static friction
Section a:
The seed is undergoes circular motion and it is been effected by centripetal acceleration.
ac = rω^2
ac = 0.078 × 3.45^2
ac = 0.9284 m/s^2
Therefore,
the centripetal acceleration of the seed is 9.274 m/s^2
Section b:
If the seed is observed not to slip at the course of the circular motion, then the supplied frictional force given by the seed and surface of turntable would at least be equivalent to the centripetal force working on the seed.
Centripetal Force = Frictional Force
mrω^2 = μsmg
μs = rω^2 /g
μs = 0.078 × 3.45^2
------------
9.81
μs = 0.09464
Thus,
the coefficient of static friction is 0.09464.
Answer: blood travels from the heart through arteries and blood travels to the heart through the veins.
I hope this helps