1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
AleksAgata [21]
2 years ago
9

Pylon cables in the National Grid have some resistance. Power (watts) = Current2 (amperes) x Resistance (ohms) Looking at the po

wer equation above, can you explain why transmitting electricity at a very high voltage is beneficial? Hint: Think about the equation Power (W) = P.D (V) x Current (A) Equation
Physics
1 answer:
lukranit [14]2 years ago
5 0

Answer: To reduce resistance in order to achieve high efficiency of electrical transmission.

Explanation: Given that the

Power P = Current I^2 x Resistance R

That is,

P = I^2 × R

Also, remember that

P = IV

Where V = voltage.

Looking at the power equations above, we can explain why transmitting electricity at a very high voltage is beneficial. Because Transmitting at very high voltage will make current to be transmitted or flow through the wire with a very small magnitude. Since Voltage is inversely proportional to current from the formula

P = IV

Electricity will flow in any diameter of cable use with a low resistance thereby, increasing the efficiency of the electricity transmission by reducing the heat that might be generated as a result of electrical resistance during the course of transmission.

You might be interested in
A toy car accelerates from 3m/s to 5m/s in 5sec . what is the acceleration​
san4es73 [151]

Answer:

0.4

Explanation:

Because 3m/s is the initial velocity(u) and 5m/s is the final velocity(v) and time is 5 sec.

So, acceleration = v-u ÷ t

I'm confused

7 0
3 years ago
A circuit consists of a battery connected to three resistors (65 ω, 25ω, and 170ω) in parallel. the total current through the re
White raven [17]
A. To find the total emf of the battery, just remember that in a parallel circuit, the voltage is the same throughout the circuit. So you can get the total voltage of the circuit by using Ohm's Law. 

I= \frac{V}{R}

Where:
I = current (A)
V = Voltage (V) (emf)
R = Resitance (Ω)

Now you can derive the formula of Voltage by transposing the Resistance to the other side of the equation to isolate Voltage. The formula you will now use will be:
V = IR

However, you cannot solve this yet because the resistance you need is the total resistance in the circuit. To do this, you need to get the total resistance in this parallel circuit and the formula would be:

\frac{1}{R_{T}} =  \frac{1}{R_{1}}+ \frac{1}{R_{2}}+ \frac{1}{R_{3}}...+ \frac{1}{R_{n}}

You have three resistors with the following resistance:
65Ω, 25Ω and 170Ω
\frac{1}{R_{T}} = \frac{1}{R_{1}}+ \frac{1}{R_{2}}+ \frac{1}{R_{3}}...+ \frac{1}{R_{n}}

\frac{1}{R_{T}} = \frac{1}{R_{65}}+ \frac{1}{R_{25}}+ \frac{1}{R_{170}}


\frac{1}{R_{T}} =0.0153+0.04+0.006+0.0059
\frac{1}{R_{T}} =0.0613

Get the reciprocal of both sides and divide:

R_{T} =  \frac{1}{0.0613} =16.32

The total resistance then is 16.32Ω

Now that you have the total resistance, you can solve for the total voltage:
V = IR
V = (1.8)(16.32)
V = 29.376V

The emf of the battery is 29.376V


B. To find the resistance in each resistor, just apply Ohm's law again. In a parallel circuit, the voltage is the same, but the current that runs through it is different for each resistor. Now just solve for the current of each using the same voltage.

Resistor 1: 65Ω
I= \frac{V}{R}
I= \frac{29.376}{65}
I= 0.45A

The current flowing through resistor 1 with a resistance of 65Ω is 0.45A.

Resistor 2: 25Ω
I= \frac{V}{R}
I= \frac{29.376}{25}
I= 1.18A
The current flowing through resistor 2 with a resistance of 25Ω is 1.18A.

Resistor 3: 170Ω
I= \frac{V}{R}
I= \frac{29.376}{170}
I= 0.17A

The current flowing through resistor 3 with a resistance of 170Ω is 0.17A.

If you add up all their current it confirms the given that the total current running through all of them is 1.8A.
4 0
3 years ago
If we want to describe work, we must have
tresset_1 [31]

The answer is C

Hope that helps!

Good luck :)

8 0
3 years ago
Read 2 more answers
How are intensity sound and energy related
zubka84 [21]
Sound is a form of energy in that it consists fluctuations of air pressure . The speed of the fluctuations is measured in cycles per second or Hertz (HZ)

Intensity is how large the fluctuations are, also known as amplitude and for the sound the unit is decibels of sonic pressure level (dB SPL)
8 0
3 years ago
A rotating light is located 13 feet from a wall. The light completes one rotation every 3 seconds. Find the rate at which the li
saveliy_v [14]

Answer:

29.2 ft/s

Explanation:

The distance of the light's projection on the wall

y = 13 tan θ

where θ is the light's angle from perpendicular to the wall.

The light completes one rotation every 3 seconds, that is, 2π in 3 seconds,

Angular speed = w = (2π/3)

w = (θ/t)

θ = wt = (2πt/3)

(dθ/dt) = (2π/3)

y = 13 tan θ

(dy/dt) = 13 sec² θ (dθ/dt)

(dy/dt) = 13 sec² θ (2π/3)

(dy/dt) = (26π/3) sec² θ

when θ = 15°

(dy/dt) = (26π/3) sec² (15°)

(dy/dt) = 29.2 ft/s

5 0
3 years ago
Other questions:
  • Consider that a ray of light is travelling from glass to water. The refractive index of water is 1.30 (i e n . ., 1.30 w = ) and
    14·1 answer
  • How does the current model of the atom differ from<br> j j thomas model
    8·1 answer
  • True or false this is for a test
    10·2 answers
  • What's a sentence using work in a nonscientific sense
    12·2 answers
  • A car with a constant velocity of 22 m/s is driven for 6.8 s. How far did it travel? (V =A d/AT)
    10·1 answer
  • The position vector of a particle of mass 1.65 kg as a function of time is given by = (6.00 î + 4.15 t ĵ), where is in meters an
    10·1 answer
  • A water tank has a square base of area 8 square meters. Initially the tank contains 70 cubic meters. Water leaves the tank, star
    14·1 answer
  • Infrared radiation from young stars can pass through the heavy dust clouds surrounding them, allowing astronomers here on Earth
    6·1 answer
  • The human eye can change the shape of its crystalline lens, and thus modify the lens strength (a.k.a., lens power) of the eye in
    13·1 answer
  • Light my fire! Mix me with cerium and we’ll make beautiful mischmetal together!
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!