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
Viktor [21]
3 years ago
10

The high electrical conductivity of copper is an important design factor that helps improve the energy efficiency of electric mo

tors. This is important because motors and motor-driven systems are significant consumers of electricity, accounting for 43% - 46% of all global electricity consumption and 69% of all electricity used by industry. Inefficient motors waste electrical energy and are indirect contributors to greenhouse gas emissions. ElectroSpark, Inc. has been developing a new copper die-cast rotor technology specifically for premium efficiency motors, replacing the standard aluminum rotor. There are multiple reasons for doing so, including the possibility that the motor will consume less energy. They designed an experiment to test their idea in a common ¾ Horse power (HP) motor that is normally manufactured with an aluminum rotor. They designed a copper rotor that fit in their ¾ HP motor housing and ran a production line for a day producing the motors. They randomly selected 20 copper-rotor motors from that output and 20 aluminum-rotor motors produced from the same line the day before. These 40 motors were all run for 8 hours a day for 30 days and the energy consumed was measured in total Kilowatt Hours (example data below, using alpha=.05):
Copper: 560.145 539.673 556.834 559.873
Aluminium: 564.674 573.912 553.385 574.078
What is the correct hypothesis to test the problem described in this scenario?
A. H0: μD (copper-aluminum) ≥ 0; H1: μD (copper-aluminum) < 0
B. H0: μ_copper – μ_aluminum ≥ 0; H1: μ_copper – μ_aluminum < 0
C. H0: μD (copper-aluminum) ≥ 0; H1: μD (copper-aluminum) > 0
D. H0: μ_copper – μ_Aluminum ≤ 0; H1: μ_copper – μ_aluminum > 0
Engineering
1 answer:
ludmilkaskok [199]3 years ago
5 0

Answer:

B

Explanation:

This is a two sample t-test and not a matched pair t-test

null hypothesis(H0) will be that mean energy consumed by copper rotor motors is greater than or equal to mean energy consumed by aluminium rotor motors

alternate hypothesis(H1) will be that mean energy consumed by copper rotor motors is less than or equal to mean energy consumed by aluminium rotor motors.

So, option D is rejected

The hypothesis will not compare mean of differences of values of energy consumed by copper rotor motor and aluminium rotor motor.

Option A and C are also rejected

You might be interested in
4.68 Steam enters a turbine in a vapor power plant operating at steady state at 560°C, 80 bar, and exits as a saturated vapor at
garik1379 [7]

Answer:

please mark me as a brainleast

Explanation:

hahahahhahaahhahahahahahahahahahahahahahahahaahhhahhhahaahahhaahhhahahaah

3 0
3 years ago
A carbon resistor has a resistance of 976 ohms at 0 degrees C. Determine its resistance at 89 degrees C​
nignag [31]

Answer:

1028.1184 Ohms

Explanation:

<u>Given the following data;</u>

  • Initial resistance, Ro = 976 Ohms
  • Initial temperature, T1 = 0°C
  • Final temperature, T2 = 89°C

Assuming the temperature coefficient of resistance for carbon at 0°C is equal to 0.0006 per degree Celsius.

To find determine its new resistance, we would use the mathematical expression for linear resistivity;

R_{89} = R_{0} + R_{0}(\alpha T)

Substituting into the equation, we have;

R_{89} = 976 + 976*(0.0006*89)

R_{89} = 976 + 976*(0.0534)

R_{89} = 976 + 52.1184

R_{89} = 1028.1184 \ Ohms

5 0
3 years ago
As resistors are added in series to a circuit, the total resistance will
olganol [36]

The equivalent of the resistance connected in the series will be Req=R₁+R₂+R₃.

<h3>
What is resistance?</h3>

Resistance is the obstruction offered whenever the current is flowing through the circuit.

So the equivalent resistance is when three resistances are connected in series. When the resistances are connected in series then the voltage is different and the current remain same in each resistance.

V eq    =    V₁    +    V₂    +    V₃

IReq    =    IR₁    +    IR₂   +    IR₃

Req    =    R₁    +    R₂   +    R₃

Therefore the equivalent of the resistance connected in the series will be Req=R₁+R₂+R₃.

To know more about resistance follow

brainly.com/question/24858512

#SPJ4

8 0
2 years ago
Infinitivo de vivia kkk xd
blagie [28]

Answer:

pls put a question not random letters

Explanation:

8 0
3 years ago
A pumping test was made in pervious gravels and sands extending to a depth of 50 ft. ,where a bed of clay was encountered. The n
Vikki [24]

Answer:per minute from the pumping well, a steady state was attained in about 24 hr. The draw-down at a distance of 10 ft. was 5.5 ft. and at 25 ft. was 1.21 ft.

Explanation:

6 0
3 years ago
Other questions:
  • There are 20 forging presses in the forge shop of a small company. The shop produces batches of forgings requiring a setup time
    10·1 answer
  • A thin-walled tube with a diameter of 6 mm and length of 20 m is used to carry exhaust gas from a smoke stack to the laboratory
    7·1 answer
  • A 1-lb collar is attached to a spring and slides without friction along a circular rod in a vertical plane. The spring has an un
    6·1 answer
  • What will the following segment of code output? score = 95; if (score &gt; 95) cout &lt;&lt; "Congratulations!\n"; cout &lt;&lt;
    9·1 answer
  • The flatbed truck carries a large section of circular pipe secured only by the two fixed blocks A and B of height h. The truck i
    14·2 answers
  • 3. Write down the total thermal resistance for a double-pipe heat exchanger. Show how to convert from total resistance to an ove
    12·2 answers
  • Tech A says that proper footwear may include both leather and steel-toed shoes. Tech B says that when working in the shop, you o
    15·1 answer
  • Is the science of measurement
    13·2 answers
  • When mass is the same, what is the relationship between radius and compression strength?
    5·1 answer
  • A 1.9-mm-diameter tube is inserted into an unknown liquid whose density is 960 kg/m3, and it is observed that the liquid rises 5
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!