Does angular speed mean how many degrees difference it turns in a second?
(for example, let's call the beginning point A the point after one second C and the center of the circle B... Are you trying to find angle ABC?)
This is my 600th post!!!!
1. A wheel has a 2cm diameter. the speed of a point on its rim is 11 m/s. What is its angular speed?
2. A horse on a merry-go-round is 7m from the center and travels at 10km/h. What is its angular speed?
3. A water wheel has a 10ft radius. The wheel revolves 16 times per minute. What is the speed of the river in mi/hr?
Does angular speed mean how many degrees difference it turns in a second?
(for example, let's call the beginning point A the point after one second C and the center of the circle B... Are you trying to find angle ABC?)
This is my 600th post!!!!
All three of these involve the formula , where v is the tangential speed, r is the radius of the motion, and is the angular speed.Originally Posted by ^_^Engineer_Adam^_^
1. r = 1 cm = 0.01 m (NOT 2 cm!), v = 11 m/s (ALWAYS check your units!)
So rad/s = 1100 rad/s.
The other two are similar. Be careful of the last one...there are a number of unit changes you need to make. My suggestion is to get the speed of the river in ft/s, then convert to mi/hr. Also to find the angular speed in problem 3, note that 16 revolutions is equal to rad.
-Dan
The angular speed is the time rate of change of the angle an object turns through. Similar to the definition of speed: angular speed is where represents the "angular position" of the rotating object.Originally Posted by Quick
Oh, and in case the units are obscure to you, 1 radian is defined as the angle marking out an arc length on a circle equal to the radius. We may calculate from this definition that radians are equivalent to 180 degrees.
-Dan
I would recomend trying to figure out a formula yourself (I do it all the time)
Here's my method:
A wheel has diameter , therefore it's circumference is
Now an object moves at a speed of around the circumference...
therefore the angular speed, for the object (in degrees) is:
which can then be converted to radians:
can you figure out how I got that answer?
Hello, ^_^Engineer_Adam^_^!
Here's #3 . . .
3. A water wheel has a 10ft radius. The wheel revolves 16 times per minute.
What is the speed of the river in mi/hr?
The circumference of the wheel is: . feet.
At 16 rev/min, a point on the wheel moves: . feet per minute.
We have: .