Hi, i am glad i have found this site. I am taking an online physics course, the kind where you read the book, work the problems, and take the test. Needless to say it has been very hard on me. I must be really dense at physics because i have purchased supplemental books but to no avail. I have a few questions on rotation and would like to know if i can get a general outline as what to do. I am not posting specific homework problems, but just the general idea of them, so i may work them out myself.(adsbygoogle = window.adsbygoogle || []).push({});

#1. Given a rotation rate in rad/sec and an accelleration rate in rad/sec^2, find:

a. Rotation rate after a given time in seconds

b. Angular displacement in radians during that time.

#2. Someone is slinging a rock of given mass around his head. Knowing the length of the sling and rotation rate find tangetial velocity of mass, centripital acceleration of rock, and tension in rope.

#3. A wheel requires a given number of radians of rotation to accelerate from rest to a given angular rotation rate (in rad/sec). Find angular rate of acceleration, time to accelerate to given rotation rate, rotation rate after x seconds.

#4. A horizontal beam is attached to a frictionless hinge on a wall. Beam weight is given. A weight is placed on the beam at a given location. A VERTICAL cable supports the beam at the outer end. Find

tension in cable

x-component of force exerted on the beam by the wall

y-component of force exerted on the beam by the wall

(that VERTICAL cable is getting me)

#5. A solid disc has a frictiionless axle running through its center, allowing it to rotate about this axis. Radius is given. Find tangetial force required to accelerate the disc from rest to a given rotation rate in a given number of seconds.

These are the main problems i am having. Sorry if these seem somewhat easy to some people, but i do not even know where to start on some of them. Thanks to anyone who helps.

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# Homework Help: Physics woes - online course - Rotation

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