Aflywheel in a motor is spinning at 520 rpm when a power failure suddenly occurs. the flywheel has mass 40.0 kg and diameter 75.0 cm. the power is off for 40.0 s, and during this time the flywheel slows down uniformly due to friction in its axle bearings. during the time the power is off, the flywheel makes 220 complete revolutions. at what rate is the flywheel spinning when the power comes back on? how long after the beginning of the power failure would it have taken the flywheel to stop if the power had not come back on, and how many revolutions would the wheel have made during this time?

Explanation:

Given that:

Initial speed of flywheel after power failure,

mass of flywheel,

diameter of flywheel,

time duration of power failure,

No. of revolutions during the power failure,

we know from the equation of motion

Negative sign indicates deceleration.

Now for the flywheel speed at the beginning of power failure we use:

.............................................(1)

where = final speed

Now using eq.(1) until the flywheel stops.

i.e.

while other conditions being the same

For this case the no. of revolution made before stopping:

answer;

d. are made mostly of liquid

explanation;

-the general   composition and structure planets includes; they have a thick gas and liquid layer covering a small,solid core. mostly the gases are hydrogen and helium atmosphere and layers of liquid hydrogen. for instance neptune and uranus are examples of the outer planets, they have a core covered by ice and ammonia.

-neptune's atmosphere is hydrogen and helium with a bit of methane so there is no oxygen to breath and the interior is made up of frozen water and ammonia with a rock and iron core. thus, there is no liquid water or solid surface to survive.

the answer is f1 and d2 because if you put equal force on those two points the beam would balance trust me on this