On a similar problem wherein instead of 480 g, a 650 gram of bar is used:
Angular momentum L = Iω, where
<span>I = the moment of inertia about the axis of rotation, which for a long thin uniform rod rotating about its center as depicted in the diagram would be 1/12mℓ², where m is the mass of the rod and ℓ is its length. The mass of this particular rod is not given but the length of 2 meters is. The moment of inertia is therefore </span>
<span>I = 1/12m*2² = 1/3m kg*m² </span>
<span>The angular momentum ω = 2πf, where f is the frequency of rotation. If the angular momentum is to be in SI units, this frequency must be in revolutions per second. 120 rpm is 2 rev/s, so </span>
<span>ω = 2π * 2 rev/s = 4π s^(-1) </span>
<span>The angular momentum would therefore be </span>
<span>L = Iω </span>
<span>= 1/3m * 4π </span>
<span>= 4/3πm kg*m²/s, where m is the rod's mass in kg. </span>
<span>The direction of the angular momentum vector - pseudovector, actually - would be straight out of the diagram toward the viewer. </span>
<span>Edit: 650 g = 0.650 kg, so </span>
<span>L = 4/3π(0.650) kg*m²/s </span>
<span>≈ 2.72 kg*m²/s</span>
C i would think
it sounds best
Answer:
10.21 N
Explanation:
As the force is a vector, it can be decomposed in two components perpendicular each other, so there is no projection of one component in the direction of the other.
When divided in this way, the magnitude of the resultant vector can be found simply applying trigonometry, as follows:
F² = Fx² + Fy² ⇒ F = √(Fx)²+(Fy)²
Replacing by Fx= 5.17 N and Fy = 8.8 N, we get:
F = √(5.17)²+(8.8)² =10.21 N
The best answer is D. The SI system, which is based on the metric system, has been more widely adopted than the English system, which is harder to use. In order to standardize measurements, the International System of Units or the SI units are commonly used around the world since they are more easy to understand and compare than the English unit.
