Answer:
371.2 mm
Explanation:
The Balmer series of spectral lines is obtained from the formula
1/λ = R(1/2² -1/n²) where λ = wavelength, R = Rydberg's constant = 1.097 × 10⁷ m⁻¹
when n = 15
1/λ = 1.097 × 10⁷ m⁻¹(1/2² -1/15²)
= 1.097 × 10⁷ m⁻¹(1/4 -1/225)
= 1.097 × 10⁷ m⁻¹(0.25 - 0.0044)
= 1.097 × 10⁷ m⁻¹ 0.245556
= 2.693 10⁶ m⁻¹
So,
λ = 1/2.693 10⁶ m⁻¹
= 0.3712 10⁻⁶ m
= 371.2 mm
Answer:
i know the first one.
Explanation:
the distance from earth in light years is 6 trillion miles.
Answer:
8.25 V
Explanation:
We can ignore the 22Ω and 122Ω resistors at the bottom. Since there's a short across those bottom nodes, any current will go through the short, and none through those two resistors.
The 2Ω resistor and the 44Ω resistor are in parallel. The equivalent resistance is:
1 / (1 / (2Ω) + 1 / (44Ω)) = 1.913Ω
This resistance is in series with the 12Ω resistor. The equivalent resistance is:
1.913Ω + 12Ω = 13.913Ω
This resistance is in parallel with the 24Ω resistor. The equivalent resistance is:
1 / (1 / (13.913Ω) + 1 / (24Ω)) = 8.807Ω
Finally, this resistance is in series with the 4Ω resistor. The equivalent resistance of the circuit is:
8.807Ω + 4Ω = 12.807Ω
The current through the battery is:
12 V / 12.807Ω = 0.937 A
The voltage drop across the 4Ω resistor is:
(0.937 A) (4Ω) = 3.75 V
So the voltage between the bottom nodes and the top nodes is:
12 V − 3.75 V = 8.25 V
Answer:
a=8.06m/s^2
Explanation:
The box can be considered negligible body slidding down along a curved path defined by the parabola Y=Ax^2
Note:
When it's at A(x=2m, y=1.6m),
the speed Vb=8m/s and the increase in speed=4m/s^2
To find the acceleration,
Y=Ax^2
dy/dx=8x
d^2y/dx^2=8
p={[1+(dy/dx)^2]^3/2}/|d^2y/dx^2| .......1
substituting into 1, we have
p=8.39624m
an=v^2/p
an=8^2/8.39624=7.6224m/s^2
a=sqrt(at^2+an^2)
a=sqrt(4^2+7.62246^2)
a=8.06m/s^2
Answer:
(C) HBr is an acid .......