How Much Distance Does a Wheel Cover in One Second?

[soharu]

Homework Statement

i know Circumference is C = pi . d
if i have a wheel that need to be rotate in given time, how much centimeter i need to rotate in 1 sec?..

Homework Equations

if i have this :
Diameter = 5cm
Circumference = 15.7cm
Given time = 60sec

The Attempt at a Solution

and i got the calculation..dunno if this right/wrong..thats y i need ur help guys..=.='

Given_Times / Circumference

Answer : 3.8217 cm / sec

*/ sorry for my bad english /*

 

[Dick]

Don't you want circumference/time?

 

[HallsofIvy]

No, he doesn't because that would have units of "time/distance". He asked "how much centimeter i need to rotate in 1 sec?" which has units of "distance/time": cm/sec.

Soharu: Yes, the circumference, in cm., divided by the time, in seconds, of one rotation will give you the speed, at the circumference, in cm/sec.

 

[Dick]

No, he doesn't because that would have units of "time/distance". He asked "how much centimeter i need to rotate in 1 sec?" which has units of "distance/time": cm/sec.

Soharu: Yes, the circumference, in cm., divided by the time, in seconds, of one rotation will give you the speed, at the circumference, in cm/sec.

Why do you say "circumference/time" would have units of "time/distance"?

 

[Jmanww]

if its circumference over time then its 15.707/60 which gives .26178 cm/sec.

 

[soharu]

if its circumference over time then its 15.707/60 which gives .26178 cm/sec.

thanx guys..now i got the result...my bad..my bad..it's cm/sec.
so the answer i got is same with the quote above..15.7/60 =
0.26718 cm/sec

 

[HallsofIvy]

Why do you say "circumference/time" would have units of "time/distance"?

Because I just plain misread what you wrote, of course!