Solve each problem. See Example 6. ...

Question

Solve each problem. See Example 6.                                                                                                                                                                                                                                                                                                         
                                                                                                                                                                                                                                                                                                                                                                         Rotating Pulley A pulley rotates through 75° in 1 min. How many rotations does the pulley make in 1 hr?

Accepted Answer

Hello, everyone. We are asked to find out the number of rotations. A wind turbine blade makes in two hours. If it rotates through 55 degrees in one minute, our answer choices are a 9. rotations. B 18.33 rotations C 36.67 rotations, D 4.58 rotations. So first we know that in one minute it goes 55 degrees. So let's figure out how far would that go in one hour. So in one hour to find that we need to do our 55 degrees multiplied by 60 for 60 minutes in an hour. And so we know in one hour this blade will rotate 3300 degrees. Since we're looking to find out how far it goes in two hours, we will take our 3300 degrees and multiply it by two. So in two hours, this blade will go 6600 degrees. We haven't answered the question just yet because we want to know how many rotations. So we need to recall that one rotation is 360 degrees. So to find out how many rotations this is we need to do the degrees in two hours divided by 360. So we'll do 6600 degrees divided by degrees. And this will tell us how many rotations did it make? And we get 18.3 repeating. It looks like all of our answer choices are rounded to two decimal places. So that's what I will do. So this means in two hours that blade will go 18.33 rotations, which is answer choice B have a nice day.

Solve each problem. See Example 6. Rotating Pulley A pulley rotates through 75° in 1 min. How many rotations does the pulley make in 1 hr?

Key Concepts

Degrees to Rotations Conversion

Rate of Rotation

Time Conversion

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