Question

Help with angles

Answer 1

A fan turns at a rate of 950 revolutions per minute. Find the angular speed of any point on one of the fan blades. Use 3.14 as an approximation for π. Express your answer in radians per second and round to the nearest tenth.

Answer 2

well we start out with an angular speed

Answer 3

angular speed is a measure of the change of an angle over time

Answer 4

revolutions are 2pi radians and minutes are a measure of time so we have angle over time which is an angular speed measurement

Answer 5

so what you need to do is convert 950 rpm to rad/s

Answer 6

you know a revolution is 2pi radians and 60s is 1min. So with that you just need to convert it

Answer 7

does this make sense or is there anything else I need to help with?

Answer 8

@recon14193 starting from the beginning with 2pi is that because 2pi=360

Answer 9

so to start i would do 950/60seconds?

Answer 10

Yes you would start with that

Answer 11

and yes it is 2pi because 2pi=360 remember a revolution is a way of saying one full turn and a full turn is the angle measure of a full circle which is 360 degrees or 2pi radians

Answer 12

@recon14193 see i dont know where to go from there. I really suck at this would you 1 revolution/2pi

Answer 13

so the way I was taught to do unit conversion aka "dimensional analysis is like this we break it up

Answer 14

so we take 950 place it over 1 since it is 950 revs in 1 min

Answer 15

we want it to cancel so we need min on top and so we use 1 min on top and so on bottom we place seconds and we know 1 min is 60 sec so we have 1 min over 60 sec

Answer 16

then we do the same thing with rev we have rev on top so we need rev on bottom in order to cancel. we know in 1 rev is 2pi rad so we have 2pi rad over 1 rev

Answer 17

then you multiply the top and divide the bottom

Answer 18

oks so in the end we would have we would have 99.5 rad/s?

Answer 19

(950*2pi)/60

Answer 20

I am getting 99.4 are you using pi as 3.14 as in the original problem or the pi button on your calculator?

Answer 21

ahhh yeh i should do that :p

Answer 22

99.48

Answer 23

use 3.14 when it says to use 3.14 other than that you are golden even though your username is dark blue. good job my friend

Answer 24

:p aha thank you could we do a few more doe with all this conversion?

Answer 25

sure

Answer 26

The minute hand of a clock is 5 inches long and moves from 12 to 7 o'clock . How far does the tip of the minute hand move? Use 3.14 as an approximation for π and round your answer to the nearest tenth.

Answer 27

so this would not be a conversion at least to my knowledge

Answer 28

what is going on here is asking how far the tip of the hand moves. The tip is moving around the rim of the clock. A clock is a circle so it is asking for the arc length

Answer 29

now do you remember the equation for arc length?

Answer 30

so would we use v=s/t?

Answer 31

I don't know if that would work. It might, and I find it interesting that you chose that equation, but for now lets stick with using the arc length equation

Answer 32

s meaning the arc length r is radius and theta is the angle\[s=\theta r\]

Answer 33

now since we know the minute hand extends to the end of the clock and is 5 inches we know r is 5

Answer 34

soh would we get the angle drawing a clock?