Answer:
= 2.83
Explanation:
F number (N) is given by the formula;
F- number = f/D
where f = focal length of lens and D = diameter of the aperture
Therefore;
F number = 17 cm/6 cm
<u> = 2.83</u>
Answer:
<em>Rt = 8 ohm</em>
<em>I = 2 A</em>
<em>Vab = 12 V</em>
<em>VbΓ = 4 V</em>
<em>VaΓ = 16 V</em>
Explanation:
<u>Electric Circuits</u>
We'll apply Ohm's formula to solve the circuit shown on the image:
V = R.I
Where V is the voltage, R is the resistance, and I is the current.
The circuit has two resistances connected in series, thus the total resistance is:
Rt = R1 + R2 = 6 ohm + 2 ohm = 8 ohm
Now the current is:
I = 2 A
The voltages are calculated below:
Vab = R1 * I = 6 ohm * 2 A = 12 V
VbΓ = R2 * I = 2 ohm * 2 A = 4 V
VaΓ = Vab + VbΓ = 12 V + 4 V = 16 V
Answer:
(a) silver
(b) 4.94 x 10^-8 ohm
Explanation:
L = 2.4 m
diameter = 5.99 mm = 5.99 x 10^-3 m
Radius, r = diameter / 2 = 2.995 x 10^-3 m
R = 1.38 x 10^-3 ohm
(a) Let ρ be the resistivity of the material
R = ρ L / A
R A / L = ρ
ρ = (1.38 x 10^-3 x 3.14 x 2.995 x 10^-3 x 2.995 x 10^-3) / 2.4
ρ = 1.62 x 10^-8 ohm-m
The material is silver.
(b) t = 1.2 mm = 1.2 x 10^-3 m
Diameter = 2.24 cm = 0.0224 m
Radius, r = 0.0112 m
Resistance, R = ρ x t / A
R = 1.62 x 10^-8 x 1.2 x 10^-3 / (3.14 x 0.0112 x 0.0112)
R = 4.94 x 10^-8 ohm