Ok, assuming "mj" in the question is Megajoules MJ) you need a total amount of rotational kinetic energy in the fly wheel at the beginning of the trip that equals
(2.4e6 J/km)x(300 km)=7.2e8 J
The expression for rotational kinetic energy is
E = (1/2)Iω²
where I is the moment of inertia of the fly wheel and ω is the angular velocity.
So this comes down to finding the value of I that gives the required energy. We know the mass is 101kg. The formula for a solid cylinder's moment of inertia is
I = (1/2)mR²
We want (1/2)Iω² = 7.2e8 J and we know ω is limited to 470 revs/sec. However, ω must be in radians per second so multiply it by 2π to get
ω = 2953.1 rad/s
Now let's use this to solve the energy equation, E = (1/2)Iω², for I:
I = 2(7.2e8 J)/(2953.1 rad/s)² = 165.12 kg·m²
Now find the radius R,
165.12 kg·m² = (1/2)(101)R²,
√(2·165/101) = 1.807m
R = 1.807m
Answer:
a) force between them is attraction, b) F = 1.125 10⁻² N
Explanation:
In this case the electric force is given by Coulomb's law
F =
In the exercise they give us the values of the loads
q1 = - 10 mC = -10 10⁻³ C
q2 = 5 mC = 5 10⁻³ C
d = 20 cm = 0.20 m
let's calculate
F = 9 10⁹
F = 1.125 10⁻² N
To find the direction of the force we use that charges of the same sign repel each other, as in this case there is a positive and a negative charge, the force between them is attraction
<span>For this example, the value presented would be considered a statistic. The value is a statistic as it represents a numerical measurement of a sample. If it were a parameter, it would need to represent a numerical measurement of a population.</span>
I dont know if it right but <span>Use a universal power adapter. This is perhaps the most obvious solution to your battery woes. Readily found at most retail outlets that carry electronics, a universal power adapter can range anywhere in price from $30 to $100 or more. The adapter comes with multiple tips, one of which will likely fit your laptop’s charging port. When plugged in, the adapter will not only power your laptop, but will charge its battery as well.</span>
Nulceus - recipe book/instruction manual
Mitochondria - Battery
Endoplasmic reticulum - Printer or a pen?
Golgi aparatus - an envelope
Chloroplasts - green rechargable battery
Cell membrane (elastic band (2 to represent the phospholipid bilayer)
Ribosomes - I guess maybe an ink pot as its the material thats used to write
Cell Wall - the paper bag
lysosomes - washing up liquid (breaks down wate food on a dirty plate)
vaculoes - bottle of water