A central air-conditioner uses 3500W of electricity. If electricity costs $0.087/kW*h. calculate how much it would cost to operate the air-conditioner 24 hours a day for 4 months (120 days).

Answers

Answer 1

Answer:

$876.96

Explanation:

The energy used is:

3500 W × (24 hr/day) × (120 day) × (1 kW / 1000 W) = 10,080 kWh.

So the cost is:

10,080 kWh × ($0.087 / kWh) = $876.96


Related Questions

what is space in detail?​

Answers

Answer:

Space in the astronomy and cosmology space is 3 dimensional region and earth atmosphere end is called space.

Explanation:

Space is the everything of the top earth atmosphere moon, starts, milky way, black hole and GPS satellites an distant,space also called between stars,moon,planet.

Space is all the extends far in all directions, space is finite unbound space surface of the earth has finite are no beginning or not end.

Space contains there are three dimensions is called 3 D space,an space is to refer an interval during signal transmitted also used by the character, bytes, words and octets in  digital signal.

space is that term can refer to various in science, communications and mathematics,and maintain orbits for responsible time, space is usually to begin at the lowest attitude satellites  can maintain orbits.

space coordinates are uniquely define the location of any particular point  and that continuum requires more than coordinates,and the number of dimensions and conventional space or digital communications during the  signal represents logic is 0 words in a digital signal.  

Solve for angles A-D

Answers

B = 53°

Reason: Opposite angles

A = 37°

Reason: Sum of angels on a straight line = 180 so 180-90-53 = 37°
C = 90°

Reason: Right angles = 90°

D = 37°

Reason: Sum of angels on a straight line = 180 so 180-90-53 = 37°


Which is
easier
Push
or pull.
when force is at angle​

Answers

Answer:

pull

Explanation:

because when you push there is one component of force that adds to tge weight of body and hence there is more friction. Whwn you pull the vertical component of force is against the weight of body and hence friction is low.

A machine can never be 100% efficient because some work is always lost due to which factor? friction gravity static input force

Answers

Explanation:

Hi,

The answer is friction.

There is almost no machine which are not affected by friction. It losts some work due to friction while working.

Hope it helps..

Answer:

friction

Explanation:

the other options dont effect efficiency

The motion of a particle along a straight line is described by the equation x=6+4t2 -t 4 , where x is in meter and t is in seconds. Find position, velocity, and acceleration of the object when t=2s.

Answers

Answer:

The position of the particle is 6m

The velocity of the particle is 16 m/s in negative direction

The acceleration of the object is -40 m/s²

Explanation:

Given;

motion of the particle along a straight line as x = 6 + 4t² - t⁴

The position of the object when t = 2s

x = 6 + 4(2)² - (2)⁴

x = 6 + 16 - 16

x = 6m

The velocity of the object when t = 2s

Velocity = dx/dt

dx/dt = 8t - 4t³

when t = 2s

Velocity = 8(2) - 4(2)³

Velocity = 16 - 32

Velocity = -16m/s

Velocity = 16 m/s (in negative direction)

The acceleration of the object when t = 2s

Acceleration = d²x/dt² = 8 - 12t²

Acceleration = 8 - 12 (2)²

Acceleration =  -40 m/s²

A small cylinder is rolled along a ruler and completes two revolutions. The circumference is the distance around the outside of a circle. What is the circumference of the cylinder? A 4.4 cm B 5.2 cm C 8.8 cm D 10.2 cm

Answers

Answer; 4.4cm

Explanation: There is a ruler upon which the cylinder start from 1.4cm and reaches 10.2cm

distance traveled =10.2-1.4=8.8

since this cylinder is small so the linear distance can be approximately taked as rotational distance(as in case of point charge) so

2x2πxr =8.8

so the circumference will be 2πr=4.4cm

 

[tex]r=s^2/t^2[/tex] 1. If s is tripled and t stays constant, r is multiplied by... 2. If t is doubled, and s stays constant, r is multiplies by...

Answers

Answer:

9 and 4

Explanation:

The relation is:

● r = s^2 / t^2

Triplind s means multiplying it by 3. Since it's an equation we should multiply both sides by the same number

Let k be the number we should multiply by r

●k* r = (3s)^2 / t^2

●k* r = 9s^2 /t^2

We have multiplied s^2 by 9 so we should do the same for r.

k = 9

■■■■■■■■■■■■■■■■■■■■■■■■■■

Doubling t means multiplying it by 2.

Let x be the number we shoukd multiply by r.

● x* r = s^2/(2t)^2

● x*r = s^2/ 4t^2

We have multiplied t^2 by 4 so we should do the same for r.

x= 4

a ferris wheel has a centripetal acceleration equal to 2m/s squared. what is the centripetal force acting on a 45 kg boy riding in one of the cars when the car is on the top of the ferris wheel? what is the force exerted by the seat on the boy when the car is at the top of the ferris wheel

Answers

Explanation:

[tex]centripetal \: force = \frac{m {v}^{2} }{r} [/tex]

Centripetal force = 45 * 2 = 90 N

Therefore, centripetal force acting on a 45 kg boy riding in one of the cars when the car is on the top of the ferris wheel is 90 N.

The force exerted by the seat on the boy when the car is at the top of the ferris wheel is a centrifugal (pseudo force) acting (since the since the seat is in non- inertial frame) in exact opposite direction (Outwards) as the centripetal force and is equal in magnitude.

Use the diagram to answer each question.


Why might a researcher further classify the data in the chimpanzee dier table to include separate information of males and females ?

Answers

Answer:

In the data table, we can see the frequency distribution in the diet of a given type of chimpanzee.

Why a researcher further classify the data separating information of males and females?

Well, the objective of the researcher is to find information about these chimpanzees, so if he notices that the diet varies (even slightly) between males and females, separating the information between males and females would be useful to know how the diet varies, and why this happens.

This is the primary motive of why a researcher would want to separate the information of males and females.

Guys, can you please answer these three questions. I'm having trouble doing them.

Answers

Answer:

17) a) 30 kg·m/s

b) 30 kg·m/s

c) 0.3 m/s.

18) 2.4 m/s

19) 360,000 N

The different make of  car is safer because the force acting on it  is 28,800 N, resulting much less impact

Explanation:

17) By conservation of linear momentum principle, we have;

m₁·v₁ + m₂·v₂ = m₁·v₁' + m₂·v₂'

Where;

m₁ = The mass of the astronaut = 100 kg

v₁ = The initial velocity of the astronaut = 0 m/s

m₂ = The mass of the equipment box = 2.5 kg

v₂ = The initial velocity of the equipment box = 0 m/s

v₁' = The final velocity of the astronaut

v₂' = The final velocity of the equipment box = 12 m/s

The final momentum of the equipment box = Mass of the equipment box × Final velocity

a) The final momentum of the equipment box = 2.5 kg × 12 m/s = 30 kg·m/s

b) Given that the box and the astronaut will move in opposite directions, we have;

m₁·0 + m₂·0 = -m₁·v₁' + m₂·v₂'

m₁·v₁' = m₂·v₂'

Therefore, the momentum of the astronaut will be equal to the momentum of the equipment box = 30 kg·m/s

c)  The velocity of the astronaut is given by th following relation;

100×0 + 2.5×0 = -100×v₁' + 2.5×12

100×v₁' = 2.5×12

v₁' = 2.5×12/100 = 30/100 = 0.3 m/s

The final velocity of the astronaut = 0.3 m/s.

18) By conservation of linear momentum principle, we have;

m₁·v₁ + m₂·v₂ = m₁·v₁' + m₂·v₂'

Where;

m₁ = The mass of the railway truck= 4000 kg

v₁ = The initial velocity of the railway truck= 8 m/s

m₂ = The mass of the stationary truck = 6000 kg

v₂ = The initial velocity of the stationary truck = 0 m/s

v₁' = The velocity of the two trucks immediately after collision

Therefore, we have;

4000 kg × 6 m/s + 6000 × 0 = (6000 + 4000) × v₁' = 10,000·v₁'

24,000 kg·m/s = 10,000·v₁'

v₁' = 24,000/10,000 = 2.4 m/s

The velocity of the two trucks immediately after collision is = 2.4 m/s

19) The change in kinetic energy of the car due to the collision = 1/2·m·(v₂² - v₁²)

The initial velocity of the car, v₁ = 12 m/s

The final velocity, v₂ = 0 m/s

The mass of the car, m= 600 kg

The time in which the car is brought to rest = 2 seconds

Initial time at point of collision, t₁ = 0 s

Time after collision, t₂ = 0.02 s

By Newton's second law of motion, we have

The force F acting on the car = Rate of change in momentum produced by the force

F = m × dv/dt

Force  = m × (v₂ - v₁)/(t₂ - t₁) = 600×(0-12)/(0.02 - 0) = -360,000 kg·m/s²

The force acting on the car  is equal and opposite to the force of the car =  360,000 N

b) For the different make of the car, we have;

m × (v₂ - v₁)/(t₂ - t₁) = 600×(0-12)/(0.25 - 0) = -28,800 kg·m/s². = -28,800 N

Therefore, the different make of  car is safer because the force acting on it  is 28,800 N, resulting much less impact.

A car is moving on straight highway with a speed of 108 km/h.

Answers

Answer:

5.3333 sec

Explanation:

initial speed: u = 108km/hr or 30 m/s

final speed: v = 0m/s

distance travelled: s = 80m

time the car took to stop: = t sec

[tex]v^{2} - u^{2}[/tex] = 2as,

a = ([tex]v^{2} - u^{2}[/tex])/2s

a = (0-900)/160

a = -5.625 [tex]ms^{-2}[/tex]

v = u + at,

t = (v - u)/a

t= (0 - 30)/(-5.625)

t = 5.3333 sec

(02.10 LC)

Which American sport stems from a combination of the British sports rugby and soccer?

Baseball

Basketball

Tennis

Football

Question 2 Multiple Choice Worth 5 points)

Answers

The answer is base ball because you run and slide in soccer and you run and slide in rugby. You also hit a Ball in soccer and you hit a ball in rugby.

Answer:

football

Explanation:

I took the 2.10 quiz and got it wrong so it must be football

(8.86 + 1.0 x 10^-3)÷3.610×10^-3​

Answers

Answer:

2454.57

Explanation:

Step 1: Solve

[tex]\frac{(8.86+0.001)}{(3.610)(10^{-3}) }[/tex]

[tex]\frac{8.861}{0.003.61 }[/tex]

2454.57

Therefor the answer to this equation is 2454.57

One end of a graphite rod is brought near a heat source. How does the other end of the rod eventually heat up? A. Directly from the heat source B. Vibrations from neighboring atoms C. Waves from the heat source D. Waves from neighboring atoms

Answers

Answer:

Vibrations from neighboring atoms

Explanation:

When a rod is heated, the thermal energy transferred to the molecules of the rod causes them to vibrate faster. As the molecules near the heat source vibrate faster, they eventually transfer their excess energy to neighbouring molecules which also begin to vibrate faster. This continues until heat is distributed throughout the length of the rod.

The process described above is known as heat transfer by conduction.

A 2.00 m long string transmits
waves at 12.9 m/s. At what
frequency will it create standing
waves with 3 loops?
(Unit = Hz)

Answers

Answer:

The frequency at which the string will create a standing wave be  with three loops is 8.6 Hz

Explanation:

The speed of the of the wave, v = 12.9 m/s

The number of loops of the standing wave = 3 loops

The length of the string = 2.00 m

Given that one loo = half of the wavelength, we have;

Three loops = 3 × half = One and half wavelength  = 1.5·λ

The frequency of a wave = f = v/λ

Therefore, we have;

The frequency, f = 12.9/1.5 = 8.6 Hz

The frequency at which the string will create a standing wave be  with three loops = 8.6 Hz.

Answer:

9.675

Explanation:

got it right on acellus

The energy change in an endothermic reaction is: A. Internal B. External C. Negative D. Positive

Answers

Answer:

Positive

Explanation:

In an endothermic reaction, the products are at a higher energy than the reactants. This means that the enthalpy change of the reaction (∆H) is positive



How much work is done in moving a body of mass 1.0 kg from an elevation of 2 m to
an elevation of ​

Answers

Answer:

The work done is -176.4 J.

Explanation:

Given that,

Mass = 1.0 kg

An elevation of  2 m to an elevation of 20 m.

Suppose,  Find the work done by the gravitational field of the earth?

We need to calculate the force

Using formula of force

[tex]F=mg[/tex]

Put the value into the formula

[tex]F=1.0\times9.8[/tex]

[tex]F=9.8\ N[/tex]

We need to calculate the displacement

Using formula of displacement

[tex]Displacement = s_{2}-s_{1}[/tex]

[tex]s=20-2=18\ m[/tex]

The direction of displacement is upward.

Since gravitational force is downwards and displacement is upwards,

Then the angle is 180°.

We need to calculate the work done

Using formula of work

[tex]W=f\cdos s\cos\theta[/tex]

[tex]W=9.8\times18\cos180[/tex]

[tex]W=-176.4\ J[/tex]

Hence, The work done is -176.4 J.

If the s – t graph of a particle is parallel to the t – axis, the speed of the particle is (a) zero (b) constant (c) infinite (d) non-uniform

Answers

Answer:

(b) constant

Explanation:

parallel to t - axis means, at all the times, the s component does not change, it remains same, i. e., the speed is constant.

:-)

Answer:

zero

Explanation:

if the velocity time graph is parallel to the time axis its mean body has not covered the path in other words body is at rest.So the velocity of the body should be zero

so the speed is zero

hope my answer will help u

A man of mass 75kg stands on a weighing machine in a lift. Determine the reading of the weighing machine when the lift is moving: 1. Upwards with an acceleration of 2m/s² 2. Downwards with a constant velocity of 1.5m/s 3. Downwards with an acceleration of 2.5m/s²

Answers

Explanation:

Given that,

Mass of a man, m = 75 kg

(1) We need to find the reading of the weighing machine when the lift is moving upwards with an acceleration of 2 m/s². When the lift is moving upward, reading of the weighing machine is given by :

R = m(g+a)

R = 75 (9.8+2)

R = 885 N

(2) When the lift is moving downwards with a constant velocity of 1.5m/s. It means that the lift is at rest. So, the reading is :

R = mg

R = 75 (9.8)

R = 735 N

(3) When the lift is moving downwards with an acceleration of 2.5 m/s². In this case,

R = m(g-a)

R = 75 (9.8-2.5)

R = 547.5 N

Hence, this is the required solution.

How to find average acceleration only using displacement and time?

Answers

Answer:

Average acceleration = Displacement / (time)^2

Explanation:

The unit for acceleration is

[tex]m {s}^{ - 2} [/tex]

Displacement = m

Time = s

Hence the units of displacement and time should be manipulated to get the unit of acceleration.

You can't. You can only find average velocity.

But if you also know that initial velocity is zero ... the object started from rest ... then

Avg acceleration =

2 x displacement / time-squared

Earth orbits 1 AU from the Sun, and the Oort cloud extends from about 10,000 to 100,000 AU from the Sun. If you represent Earth’s orbit around the Sun with a paper plate 4 inches in radius, how far away will the inner edge of the Oort Cloud be? The outer edge? Express your answers in miles.

Answers

Explanation:

Earth’s orbit around the Sun represented as :

1 AU = 4 inches

Therefore,

Inner edge of the Oort Cloud represented as :

10,000 AU = 40,000 / 63360 = 0.631 miles

Outer edge of the Oort Cloud represented as:

100,000 AU = 400,000 / 63360 = 6.31 miles

You are the driver of the car in the photos above. You Are traveling at 30 mph when suddenly the car goes from its position in the first photo to the position in the second photo. What is happening

Answers

Answer:

the car uses teleportation, to zip to one side of the photo, to the other

Explanation:

What is the approximate pressure of a storage cylinder of recovered R-404A that does not contain any non-condensable impurities and is stored in a room where the temperature is 80°F?A. 68 psigB. 72 psigC. 174psigD. 288 psig

Answers

Answer:

D. 288 psig

Explanation:

The storage cylinder of recovered R-404A is a mixture of R-125, R-143 and R-134. The refrigeration sector has low temperatures for installation. The pressure of cylinder at 80 F will be 288 psig. The pure refrigerants have inside a container have saturation temperature which is equal to ambient temperature.

If you look at faint stars, you can see them more easily on the edges of your vision than if you try to look directly at them. Why is this true?

Answers

Answer:

The retina comprises of rod and cone cells . The rod cells are responsible for black and white vision and require low light levels while the cone cells are responsible for color vision and require good/high light levels for better functioning.

When faint stars are looked at on the edges of the vision it allows more light from faint objects to strike the rod cells which then becomes more visible.

Which statement best describes semi-conductors? Lack free electrons that can move to other atoms Electrons within their atoms are strongly held by the nuclei Most electrons within their atoms are paired Electricity can flow through it under special conditions

Answers

Answer:

Option D (Electricity can flow through it under special conditions ) seems to be the correct choice.

Explanation:

A semiconductor has become a crystal substance with improved electrochemical properties although the temperature is increased. That would be to say, it often functions as an insulating material rather than as a conductor or a circuit. Chemical solvents could perhaps greatly enhance its conducting capacity.

Other options that are provided are not related to the given theory. So that the above would be the correct choice.

Statement "Lack free electrons that can move to other atoms " describe semi-conductor.

Properties of Semiconductor:A semiconductor is a type of crystalline solid that is halfway between a conductor and an insulator in terms of electrical conductivity. A semiconductor is conducting in nature because it has free electrons and holes.So that, Lack free electrons that can move to other atoms.

Learn  more about the Semiconductor here:

https://brainly.com/question/1918629

If a gas and a liquid are both at the same temperature, the particles of gas have a higher average kinetic energy. True or false?

Answers

Answer:

True

Explanation:

The average kinetic energy is the measure of how freely the molecules of a substance moves relative to the other molecules within the substance. Gas and liquids are together termed fluids,  but the molecules of a gas naturally has more more average kinetic energy that that of a liquid, if they are kept at the same temperature. This explains why gases are easy to expand, and have to be confined by a container. So the particles of a gas has more kinetic energy that that of a liquid even if they are kept at the same temperature.

Will mark as BRAINLIEST.... Plz answer the 44. Ques

Answers

Answer:

T= 2.66 seconds

Explanation:

Convert 80 km to m, which would be 0.08 m

[tex]t = d \div s[/tex]

[tex]t = 0.08 km\div 108kmph[/tex]

[tex]t = 0.00074074074 \: h[/tex]

[tex]1 \: hour = 3600 \: sec[/tex]

[tex] \frac{1}{3600} \times \frac{0.00074}{x} [/tex]

[tex]0.00074074074h \times 3600s = 2.66s[/tex]

Se suelta un cuerpo desde la azotea de un edificio de 180m de alto. Luego de 3s se lanza verticalmente hacia abajo otro cuerpo. Si ambos llegan simultáneamente al piso, calcular la rapidez con la que fue lanzado el segundo cuerpo (g=10m/s2).

Answers

Answer:CcCcccccc

Explanation:

Rfsgqh

Answer answer answer it it it

Answers

Answer:

(B) Parachutes

Explanation:

Air resistance works to slow down trains and airplanes, so it isn't desirable.  Air resistance also causes pendulums to slow and stop.

Parachutes need air resistance to slow a person's fall.  So air resistance is desirable here.

Answer:

B i answered it it it

Explanation:

A skydiver falls toward the ground at a constant velocity. Which statement best applies Newton’s laws of motion to explain the skydiver’s motion? An upward force balances the downward force of gravity on the skydiver. The skydiver’s inertia is zero, which no longer allows for acceleration. An unbalanced force pulls the skydiver toward the ground. The mass of the skydiver is so great that there is no acceleration

Answers

Answer: A) an upward force balances the downward force of gravity on the skydiver

Explanation: I got it correct on my test on edge

The statement best applies Newton’s laws of motion to explain the skydiver’s motion an upward force balances the downward force of gravity on the skydiver. Thus, option A is correct.

Which statement best applies Newton’s laws of motion?

The statement that best applies Newton’s laws of motion to explain the skydiver’s motion is that an upward force balances the downward force of gravity on the skydiver. Newton's 3rd law often applies to skydiving.

When gravity is not acting upon the skydivers they would continue moving in the direction the vehicle they jumped from was moving. If no air resistance takes place, then the skydivers would still accelerating at 9.8 m/s until they hit the ground.

The skydiver after leaving the aircraft will accelerates downwards due to the force of gravity usually as there is no air resistance acting in the upwards direction, and there is a resultant force acting downwards, the skydiver will accelerates towards the ground.

Therefore, The statement best applies Newton’s laws of motion to explain the skydiver’s motion an upward force balances the downward force of gravity on the skydiver. Thus, option A is correct.

Learn more about skydiver on:

https://brainly.com/question/29253407

#SPJ6

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