This is the direction of the tension in a string when you twirl a ball in a circle above your head.
What is toward the center?
This is the type of picture that can (should) be drawn for any dynamics problem.
What is a free-body diagram?
This is what must be true for an object to be in rotational equilibrium.
What is net torque equals zero?
This is the Newton's 3rd law pair for the weight of an object on Earth.
What is the force the object pulling on the Earth?
When THIS equation is true we know that an object is rolling without slipping.
What is v = r(omega)
An isolated satellite with rotational inertia I is initially spinning with constant angular velocity ωi when it suddenly extends several antennae, causing its rotational inertia to increase to 3I. After the antennae are extended, the satellite has what angular speed?
What is ωf = ωi/3 ?