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>
Your brother would be described as a speeder.
The answer is C. It would look similar to the graph for KNO3
The Atomic Number is equal to the amount of Protons and Electrons. To find the amount of Neutrons in an atom, you have to look at the Mass Number. The Mass Number is the SUM (_+_=_) of Protons and Neutrons in an atom. In this case, you will have to make up equations. For example: Argon. Argon's Mass Number is 40. You need to find the amount of Protons in the atom (18). Mass Number (40) - Protons (18) = Amount of Neutrons. 40-18=22.
Argon has 22 Neutrons, because Protons(18)+Neutrons(22)=Mass Number(40).
Hope I could help!
The answer is B
explanation
