At STP, 1 mole of an ideal gas occupies a volume of about 22.4 L. So if <em>n</em> is the number of moles of this gas, then
<em>n</em> / (19.2 L) = (1 mole) / (22.4 L) ==> <em>n</em> = (19.2 L•mole) / (22.4 L) ≈ 0.857 mol
If the sample has a mass of 12.0 g, then its molecular weight is
(12.0 g) / <em>n</em> ≈ 14.0 g/mol
Answer:
proportional to the current in the wire and inversely proportional to the distance from the wire.
Explanation:
The magnetic field produced by a long, straight current-carrying wire is given by:
where
is the vacuum permeability
I is the current intensity in the wire
r is the distance from the wire
From the formula, we notice that:
- The magnitude of the magnetic field is directly proportional to I, the current
- The magnitude of the magnetic field is inversely proportional to the distance from the wire, r
Therefore, correct option is
proportional to the current in the wire and inversely proportional to the distance from the wire.
DRAG is the sum of all the aerodynamic or hydronamic forces in the direction of the external fluid flow.
Answer:
4816N
Explanation:
Height = 3m
Mass = 70kg
g = 9.8m/s²
S = 50cm = 0.5m
The total force = the weight of the body + impact force.
Impact force = ma but a = v / t
Using equation of motion,
V² = u² + 2as
V² = u² + 2gh
But u = 0m/s (since the body is at rest)
V² = 0 + 2 * 9.8 * 3
V² = 58.8
V = √(58.8)
v = 7.668m/s ≈ 7.67m/s
The impact interval = ?
Average velocity = total distance / time taken
V = 2s / T
T = (2 * s) / v
T = (2 * 0.5) / 7.67
T = 1 / 7.67
T = 0.13 seconds
The total force F = (mg + ma)
But a = v / t
F = m(g + v / t )
F = 70 * [ 9.8 + (7.67/0.13)]
F = 70 * (9.8 + 59)
F = 4816N
