B because the skater is constantly moving in the same speed to go in a circle .
Complete Question
A flywheel in a motor is spinning at 510 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 210 complete revolutions. At what rate is the flywheel spinning when the power comes back on(in rpm)? 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?
Answer:

Explanation:
From the question we are told that:
Angular velocity 
Mass 
Diameter d 
Off Time 
Oscillation at Power off 
Generally the equation for Angular displacement is mathematically given by




Generally the equation for Time to come to rest is mathematically given by



Therefore Angular displacement is


The formula for this problem that we will be using is:
F * cos α = m * g * μs where:F = 800m = 87g = 9.8
cos α = m*g*μs/F= 87*9.8*0.55/800= 0.59 So solving the alpha, find the arccos above.
α = arccos 0.59 = 54 ° is the largest value of alpha
Answer:
Electrical Resistance is a measure of the opposition to current flow in an electrical circuit
Types: variable resistance and set resistance
Explanation:
Some of the reasons that can cause can earthquake are volcanic eruptions, the grinding of tectonic plates beneath the earth's crust and violent explosions which can be artificially induced as well. No matter what the reason is, earthquakes affect the environment and earth's surface. Noticeable cracks have formed on the earth's surface after earthquakes. If the tremors are violent, it can result in the destruction of landscapes. The mountains become prone to land sliding. the glacier's become a threat because of fear of avalanches. tsunamis which are earthquakes in the ocean bed can cause heavy flooding which causes water to cross all boundaries and shores and flood entire cities. Earthquakes caused by volcanoes can result in the spewing of so much lava that it may spill everywhere and cool changing the surface of the earth geologically as well as the ash causing aerial pollution.