moment of inertia

"Calculate the moment of inertia of a 14.0 kg sphere of radius 0.645 m when the axis of rotation is through its center." I thought the equation was simply: I = mr^2 = (14.0)(0.645)2 = 5.82 kg*m^s but that's not the answer.

torque

"A helicopter rotor blade can be considered a long thin rod, as shown in figure below. If each of the three rotor helicopter blades is L = 3.63 m long and has a mass of m = 156 kg, calculate the moment of inertia of the three rotor blades about the axis of rotation. (ANSWER ALREADY DETERMINED TO BE 2060 kg m^2.) How much torq ...continues

noninertial reference systems

noninertial reference systems

orbit of particle moving in a central field

orbit of particle moving in a central field

finding apsidal angle for nearly circular orbits

finding apsidal angle for nearly circular orbits

Simple Harmonic Motion related problem

Determine an appropriate step size h by assuming that an h that works as expected for simple harmonic motion is good enough for the given initial angle. In particular, if the position at the end of one period is within 0.1% of the original point, we'll be satisfied.

A block of mass M, held stationary on a frictionless plane.. Find mass M and cord tension.

A block with unknown mass M is held stationary on a frictionless plane inclined at angle b= 30 degrees, by a cord attached to the ceiling. The angle between cord and ceiling is angle a=50 degrees. The normal force exerted on the block by the plane is N= 74 nt. SEE ATTACHMENT #1 for arrangement. Part a. On the diaqram shown as ...continues

word problem

a 25kg block is initially at rest on a rough, horzontal surface. A horizontal force of 75N is required to set the block in motion. After it is in motion, a horzontal force of 60N is required to keep it in motion. A.calculate the coefficient of static friction B. calculate the coefficent of kinetic friction C. If the origi ...continues

Word Problem

A 5kg block free to move on a horizontal surface is attached to a spring. The spring is compressed 0.1m from equilibrium and then released. The speed of the block is 1.2m/s at the unstressed equilibrium position of the spring. The same experiment is now repeated on a surface with a coefficent of kinetic friction = 0.3. A. ...continues

Word prob

A 200 gram mass is attached to the end of a light unstressed vertical spring (k = 80 N/m) and then dropped. A. How far will the mass drop before coming to rest momentarily>