Answer:
Explanation:
a )
moment of inertia of hollow ball
= 2 / 3 mR² , m is mass and R is radius of the ball
= 2 / 3 x 120 x .5²
= 20 kg m²
b )
5 rpm = 5 / 60 rps
n = .0833
angular velocity ω = 2πn= 2 x 3.14 x .0833= .523 rad /s
angular acceleration = increase in angular velocity / time
= .523 - 0 / 20
α = .02615 rad /s²
c )
Torque = moment of inertia x angular acceleration
= 20 x .02615
= .523 Nm
d )
θ = 1/2 α t²
= .5 x .02615 x 20²
= 5.23
2π n = 5.23 where n is required number
n = .83
Answer:
A=z+n
A=20+20
A=40
Explanation:
Not sure if I'm correct but I was taught that mass number is calculated by A=z+n where A is the mass number, z is the proton number and n is the number of neutrons.
Answer: D
Explanation: It says that in the paragraph
There may be an esoteric technical shade or nuance of difference. But I've been an electrical engineer for 40 years now, and have always used them interchangeably.
(I would have answered your question by saying "No.", but this website won't accept an answer that's less than 200 characters long.)
