Angular Momentum
The momentum of an object is given by multiplying its mass and velocity. Momentum is a property of any object that moves with mass. The only difference between angular momentum and linear momentum is that angular momentum deals with moving or spinning objects. A moving particle's linear momentum can be thought of as a measure of its linear motion. The force is proportional to the rate of change of linear momentum. Angular momentum is always directly proportional to mass. In rotational motion, the concept of angular momentum is often used. Since it is a conserved quantity—the total angular momentum of a closed system remains constant—it is a significant quantity in physics. To understand the concept of angular momentum first we need to understand a rigid body and its movement, a position vector that is used to specify the position of particles in space. A rigid body possesses motion it may be linear or rotational. Rotational motion plays important role in angular momentum.
Moment of a Force
The idea of moments is an important concept in physics. It arises from the fact that distance often plays an important part in the interaction of, or in determining the impact of forces on bodies. Moments are often described by their order [first, second, or higher order] based on the power to which the distance has to be raised to understand the phenomenon. Of particular note are the second-order moment of mass (Moment of Inertia) and moments of force.
Yesterday you saw in the news that the Giant Asian Murder Hornet has migrated to North America. You didn't think much about it until today when one of those suckers crashed at high speed into the screen door at the back of your house (splat!). The thing hit the door so hard that the door swung shut!
We will assume that GAMH had a mass of m = 0.069 kg and was moving with an amazing velocity of v = 9.2 meters/second. The GAMH splatted a distance d = 0.65 meters from the hinge. The door itself can be treated as a rod of mass M = 0.955 kg with a length of L = 1.00 meters rotating about its end.
Determine all the following:
Write the FORMULA for the moment of inertia of the door without the hornet: I =
kg m2
Write the FORMULA for the moment of inertia of the door with the hornet: I =
kg m2
Determine the
Determine the
Determine the time required for the door to close: t(? = ?/2) = seconds
Trending now
This is a popular solution!
Step by step
Solved in 3 steps with 3 images
