Assuming that the densities of the gases are:
density of air, ρ1 = 1.29 kg / m^3
density of helium, ρ2 = 0.179 kg / m^3
Since buoyant force and weight are two forces that are in
opposite direction (buoyant force is up while weight is down), therefore equate
the two:
buoyant force = weight
m g = (800 + m1) g
where m is the mass of buoyancy, g is gravity and m1 is
the maximum mass of the cargo
m = 800 + m1
We know that mass is also expressed as:
m = ρ V
where ρ is density of gas and V is volume of the sphere
Since there are two interacting gases here, therefore m
is:
m = (ρ1 – ρ2) V
Therefore:
(ρ1 – ρ2) V = 800 + m1
(1.29 – 0.179) (4π/3) (8.35m)^3 = 800 + m1
2709.33 = 800 + m1
m1 = 1,909.33 kg
Answer:
a) 1.25e15 kg
b) 4.17e20 J
c) 44.55 years
Explanation:
To find the volume you need to multiply 218 km * 25 km * 250 m (be careful with units), so the volume is 1.3625e12 m^3, if you multiply this value by the density you will obtain the mass, that is 1.25e15 kg.
To find the energy needed to melt the ice, you use the latent heat, in this case, it is 3.34e5 J/kg. Now you multiply this value by the mass, so you need 4.17e20 J to melt the iceberg.
The surface area of the iceberg is 545e7 m^2, so the ice absorbs 594e9 W, one W is one J/s, so in 12 hours the iceberg absorbs 2.56e16 J, so in 365 days absorbs 9.36e18 J. Now you just divide 4.17e20 J by the amount f energy per year, and obtain 44.55 years.
The right half will be a new bar magnet of 2cm with north pole on the right side and south pole on teh left.
Answer:
When you don't move, you still use energy. This energy is called potential energy, or, stored energy.
When you don't move or do work, you can use energy.
Distance = (speed) x (time)
Distance = (20 m/s) x (500 s)
Distance = (20 x 500) (m·s / s)
Distance = 10,000 m
