Explanation:
Power of electric kettle, P = 1 kW
Voltage, V = 220 V
(a) Electric power is given by the formula as follows :

R is resistance

(b) When connected to a 220 V supply, it takes 3 minutes for the water in the kettle to reach boiling point.
Energy supplied is given by :

P is power, 

The rms current in the transmission lines is I = 487.18 A.
The root-imply-rectangular (rms) voltage of a sinusoidal supply of electromotive force is used to represent the source. it is the rectangular root of the time average of the voltage squared.
Alternating-present day circuits. the root-imply-square (rms) voltage of a sinusoidal source of electromotive force is used to symbolize the supply. it's far the square root of the time average of the voltage squared.
Electric power is by using present day or the waft of electric fee and voltage or the capacity of rate to deliver electricity. A given cost of power can be produced by using any combination of contemporary and voltage values
power = 38 M watt
rms voltage = 78 K v
power = IV
I = power/V
I = (38 * 1000000)/78*1000
I = 487.18 A.
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Answer:
I = 21.13 mA ≈ 21 mA
Explanation:
If
I₁ = 5 mA
L₁ = L₂ = L
V₁ = V₂ = V
ρ₁ = 1.68*10⁻⁸ Ohm-m
ρ₂ = 1.59*10⁻⁸ Ohm-m
D₁ = D
D₂ = 2D
S₁ = 0.25*π*D²
S₂ = 0.25*π*(2*D)² = π*D²
If we apply the equation
R = ρ*L / S
where (using Ohm's Law):
R = V / I
we have
V / I = ρ*L / S
If V and L are the same
V / L = ρ*I / S
then
(V / L)₁ = (V / L)₂ ⇒ ρ₁*I₁ / S₁ = ρ₂*I₂ / S₂
If
S₁ = 0.25*π*D² and
S₂ = 0.25*π*(2*D)² = π*D²
we have
ρ₁*I₁ / (0.25*π*D²) = ρ₂*I₂ / (π*D²)
⇒ I₂ = 4*ρ₁*I₁ / ρ₂
⇒ I₂ = 4*1.68*10⁻⁸ Ohm-m*5 mA / 1.59*10⁻⁸ Ohm-m
⇒ I₂ = 21.13 mA
The name and strength of the force holding the block up is 50 N upward - Normal force.
The given parameters:
- <em>Mass of the block, m = 5 kg</em>
The weight of the block acting downwards due to gravity is calculated as follows;
W = mg
where;
- <em>g is acceleration due to gravity = 10 m/s²</em>
W = 5 x 10
W = 50 N <em>(</em><em>downwards</em><em>)</em>
Since the block is at rest, an a force equal to the weight of the block must be acting upwards. This force is known as normal reaction.
Fₙ = 50 N <em>(</em><em>upwards</em><em>)</em>
Thus, the name and strength of the force holding the block up is 50 N upward - Normal force.
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The time taken for the first p-wave to reach the same seismic station is approximately 13 minutes.
<h3>Time of travel of the P-wave</h3>
In rock, S waves generally travel about 60% the speed of P waves, and the S wave always arrives after the P wave.
<h3>Relationship between speed and time</h3>
v ∝ 1/t
v₁t₁ = v₂t₂
t₁/t₂ = v₂/v₁
t₁/t₂ = 0.6v₁/v₁
t₁/t₂ = 0.6
t₁ = 0.6t₂
t₁ = 0.6 x 22 mins
t₁ = 13.2 mins
Thus, the time taken for the first p-wave to reach the same seismic station is approximately 13 minutes.
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