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Twilit_Truth
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OK, I can't figure this out either. Sorry if it seems I'm here alot, I'm trying to make up 6 weeks worth of work. I have 4 problems here. I have no idea how to even begin these problems, so ANYTHING would be helpful. (s^2 is seconds squared)
1) A wheel rotates with a constant acceleration of 3.50 rad/s^2. If the angular speed of the wheel is 2.00 rad/s at ti = 0:
a) Trough what angle does the wheel rotate in 2.00s?
b) What is the angular speed at t = 2.00s?
2) Mateo rode a unicycle with a wheel diameter of .406m. If the wheel's average angular acceleration was 0.552 rad/s^2, how long will it take for the wheel's angular speed to increace from 2.39 rad/s to 5.20 rad/s?
3) In the biblical story, little David slew the Giant Goliath with a sling shot. Assume that David starts rotating a .150 kg stone from rest in a sling of radius 1.50 m. If the average angular acceleration of the stone is 4.5 rad/s^2:
a) What is the tension in the sling after 8.5 s?
b) What is the linear velocity of the stone if he releases it at 8.5 s?
4) In a typical CD player, the disc spins counterclockwise, and the speed of the surface at the point of contact of the laser lens is 1.3 m/s. This requires that the rotational speed vary with the radiuis of the track being played.
a) Find the angular speed of the disc in both rad/s and RPM (rotations/min.) when information is being read from the innermost track (r = 23 mm) and the outermost track (r = 58 mm)
b) The maximum playing time of a standard music CD is 74 min. 33 s. How many revolutions does the disc make during that time? Assume constant angular acceleration.
c) What is the total length of the track that is read by the laser during the 74 min. 33 s of playing time?
I know it's a lot, but I'm going to fail if I don't get help. Thank you for your time.
1) A wheel rotates with a constant acceleration of 3.50 rad/s^2. If the angular speed of the wheel is 2.00 rad/s at ti = 0:
a) Trough what angle does the wheel rotate in 2.00s?
b) What is the angular speed at t = 2.00s?
2) Mateo rode a unicycle with a wheel diameter of .406m. If the wheel's average angular acceleration was 0.552 rad/s^2, how long will it take for the wheel's angular speed to increace from 2.39 rad/s to 5.20 rad/s?
3) In the biblical story, little David slew the Giant Goliath with a sling shot. Assume that David starts rotating a .150 kg stone from rest in a sling of radius 1.50 m. If the average angular acceleration of the stone is 4.5 rad/s^2:
a) What is the tension in the sling after 8.5 s?
b) What is the linear velocity of the stone if he releases it at 8.5 s?
4) In a typical CD player, the disc spins counterclockwise, and the speed of the surface at the point of contact of the laser lens is 1.3 m/s. This requires that the rotational speed vary with the radiuis of the track being played.
a) Find the angular speed of the disc in both rad/s and RPM (rotations/min.) when information is being read from the innermost track (r = 23 mm) and the outermost track (r = 58 mm)
b) The maximum playing time of a standard music CD is 74 min. 33 s. How many revolutions does the disc make during that time? Assume constant angular acceleration.
c) What is the total length of the track that is read by the laser during the 74 min. 33 s of playing time?
I know it's a lot, but I'm going to fail if I don't get help. Thank you for your time.