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
pogonyaev
4 years ago
9

Why do some ceiling lights do not have an earth wire?

Physics
1 answer:
koban [17]4 years ago
5 0

Answer: Answer Below

Answer below

Explanation:

Some appliances - such as vacuum cleaners and electric drills - do not have an earth wire. This is because they have plastic casings, or they have been designed so that the live wire cannot touch the casing. ... These appliances have double insulation.

You might be interested in
Insulators will:
nalin [4]

Answer:

Inhibit the flow of electrons  

Explanation:

An electric current usually consists of electrons moving through a wire.

An insulator prevents the flow of an electric current, so it inhibits the flow of electrons.

7 0
4 years ago
Read 2 more answers
Two resistances, R1 and R2, are connected in series across a 9-V battery. The current increases by 0.450 A when R2 is removed, l
Rina8888 [55]

Answer:

a. R1 = 0.162 Ω

b. R2 = 0.340 Ω

Explanation:

Since the resistors R1 and R2 are connected in series, the current flowing through them when the 9 V battery is applied is 9/R1 + R2.

When the current increases by 0.450 A wen only R1 is in the circuit, the current is

9/R1 + R2 + 0.450 A = 9/R1       (1)

When the current increases by 0.225 A when only R2 is in the circuit, the current is

9/R1 + R2 + 0.225 A = 9/R2       (2)

equation (1) - (2) equals

9(1/R1 - 1/R2) = 0.450 A - 0.225

9(1/R1 - 1/R2) = 0.125

(1/R1 - 1/R2) = 0.125 A/9 = 0.0138

1/R1 = 0.0138 + 1/R2

R1 = R2/(1 + 0.0138R2)     (3)

From (1)

9/R1 - 9/R1 + R2 = 0.450 A

9R2/[R1(R1 + R2)] = 0.450 A

R2/[R1(R1 + R2)] = 0.450 A/9 = 0.5

R2/[R1(R1 + R2)] = 0.5    (4)

From (3) R2/R1 = (1 + 0.0138R2) and from (4) R2/R1 = 0.5(R1 + R2). So,

(1 + 0.0138R2) = 0.5(R1 + R2)

0.5R1 + 0.5R2 = 1 + 0.0138R2

0.5R1 = 1 + 0.0138R2 - 0.5R2

0.5R1 = 1 - 0.4862R2        (5)

Substituting (3) into (5) we have

0.5R2/(1 + 0.0138R2) = 1 - 0.4862R2

R2 = (1 + 0.0138R2)(1 - 0.4862R2)

R2 = 1 - 0.4724R2 - 0.0067R2²

Collecting like terms, we have

0.0067R2² + 0.4724R2 + R2 - 1 = 0

0.0067R2² + 1.4724R2 - 1 = 0

Using the quadratic formula,

R_{2} = \frac{-1.4724 +/-\sqrt{(1.4724)^{2} - 4 X 0.0067 X -1} }{2 X 0.0067}  \\= \frac{-1.4724 +/-\sqrt{2.1680 + 0.0268} }{0.0268}\\= \frac{-1.4724 +/-\sqrt{2.1948} }{0.0268}\\= \frac{-1.4724 +/- 1.4815 }{0.0268}\\= \frac{-1.4724 + 1.4815 }{0.0268} or \frac{-1.4724 - 1.4815 }{0.0268}\\= \frac{0.0091 }{0.0268} or \frac{-2.9539}{0.0268}\\= 0.340 or -110.22

We choose the positive answer.

So R2 = 0.340 Ω

From (5)

R1 = 0.5 - 0.9931R2

   = 0.5 - 0.9931 × 0.340

   = 0.5 - 0.338

   = 0.162 Ω

a. R1 = 0.162 Ω

b. R2 = 0.340 Ω

5 0
3 years ago
I need help please and thanks
asambeis [7]

Answer:

c

Explanation:

6 0
3 years ago
if a body of mass 2kg travels with 2 m/s and other body of mass 2kg travels with 1m/s then find v1 and v2 in given statement​
KIM [24]

Answer:

Your answer is here,

Explanation:

v1 = 4 kg m/s

v2 = 2 kg m/s

8 0
3 years ago
Name of compounds<br>a. H2Co3<br>b. NH4OH<br>c.AlPO4<br>d.NaOH<br>e.AuCI3<br>​
seraphim [82]

Answer:

<em><u>a) </u></em><em><u> </u></em><em><u>Carbonic acid</u></em>

<em><u>b</u></em><em><u>)</u></em><em><u> </u></em><em><u>ammonium hydroxide</u></em>

<em><u>c</u></em><em><u>)</u></em><em><u> </u></em><em><u>Aluminum phosphate</u></em>

<em><u>d</u></em><em><u>)</u></em><em><u> </u></em><em><u>Sodium hydroxide</u></em>

<em><u>e</u></em><em><u>)</u></em><em><u> </u></em><em><u>Gold trichloride</u></em>

Explanation:

<em>I</em><em> </em><em>hope this</em><em> </em><em>will help</em><em> </em><em>you</em><em> </em><em>buddy</em><em> </em>

3 0
3 years ago
Other questions:
  • Which one is it ASAP
    12·1 answer
  • How does the planet Venus look to a person standing on the Earth?
    14·1 answer
  • ___ consist of silicon chips and an antenna that can transmit data to a wireless receiver while _____ need to be scanned manuall
    8·1 answer
  • If you fire a gun horizontally, and at the same time drop a bullet/slug from the same height, what will happen?
    13·1 answer
  • How many times should the power develop by the engine of a ship increases to double is velocity i the resistance of the water to
    7·1 answer
  • A bullet that has been too badly mutilated to mark can be
    7·1 answer
  • The theory that attitudes will be formed and changed according to one’s actual behaviors is the __________ theory. A. learning B
    11·2 answers
  • A 10v battery is connected in series with 2 resistors. R1 is 1 ohm and R2 is 4 ohms. What is the current that goes across R1?
    5·1 answer
  • Can someone explain please <br> ???
    10·1 answer
  • the volume of a water tank is 5m×4m×2m. If the tank is half filled with water. calculate the pressure exerted at the bottom of t
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!