A CD has a diameter of 12.0 cm, if the CD is rotating at constant freq of 4.0 cyles per second, then the period of the rotational motion is??
Also, a CD has a diameter of 12.0 cm. If the CD is rotating at a constant angular speed of 200 revolutions per minute, then the tangential velocity of a point on the circumference is???
2 different questions, if you can help that would be great, best answer will get 10 points!! thanks!!
2007-03-10 04:25:33 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Well, the first question is kind of easy, you just need to remember that the period is 1/ F. Where "F" is the frequency
In the problem, the frequency is 4 cycles per second, then :
F = 4 c/s >>> T = 1 / 4 (s)
On the second problem you need to find the tangential velocity.
Vt = w.r
w = 200 RPM >>> 200*2pi / 60 = 40pi/6 rad / s
diameter = 12, then radius = 6 cm
Vt = (6/100)*40*pi/6 = 2pi / 5 (m/s)
Hope that might help you
2007-03-10 05:45:41 · answer #1 · answered by anakin_louix 6 · 0⤊ 0⤋
If the CD rotates 4 times per second, it will do one period in 1/4 of a second... period = 0.25 s
The circumference of the CD is 2Pi*R = 2*3.14*12 = 75.4 cm
A point on the circumference will have tangential speed of 200 x 75.4cm per minute = 15080 cm/min = 251 cm/s
2007-03-10 04:54:50 · answer #2 · answered by catarthur 6 · 0⤊ 0⤋
The formula for centrifugal tension (that's what you experience while spinning) is F=Rw^2. in this, R is your distance from the axis of rotation and w is the perspective this is grew to become around in one 2d. For the case of the earth, even nevertheless R is super (4000 miles), the w is extremely small (the quantity the earth rotates in one 2d isn't very plenty). besides, w is squared, so as that makes the stress even smaller. the tip consequence is that the stress is small. Now, the speed of rotation is v=Rw. this continues to be super for the earth (back, R is super and w is small). you will see that F=v*w. even nevertheless v is super, w is small and the product is small. those asserting that there is not any acceleration are incorrect. there is, in spite of if this is a transformation in course, no longer a transformation in velocity. This nonetheless reasons a tension. this is merely that for the earth, that tension is small.
2016-12-14 15:34:39 · answer #3 · answered by bremmer 4 · 0⤊ 0⤋
If the CD rotates 200 rev per minute, it will do it in a period of 0.3 seconds because :
200 rev = 60s
t= 0.3
Vcentripedal = 2pir/t = 2x0.06mxpi/0.3 = 1.256 m/s
2016-07-25 14:56:52 · answer #4 · answered by nada 1 · 1⤊ 0⤋