Answer:
a. E = 900000 J = 900 KJ
b. ΔT = 8.18 °C
c. Cost = $ 7.2
Explanation:
a.
The energy can be given by:
[tex]E = Pt[/tex]
where,
E = Energy = ?
P = Power = 500 W
t = time = (0.5 h)(3600 s/1 h) = 1800 s
Therefore,
[tex]E = (500\ W)(1800\ s)[/tex]
E = 900000 J = 900 KJ
b.
The change in temperature of room air is given by the following formula:
[tex]0.5E = mC\Delta T\\[/tex] (since 50% of energy is used to heat air)
where,
m = mass of air = 50 kg
C = specific heat of air = 1.1 KJ/kg.°C
ΔT = Change in temperature of air = ?
Therefore,
[tex](0.5)(900\ KJ) = (50\ kg)(1.1\ KJ/Kg.^oC)\Delta T[/tex]
ΔT = 8.18 °C
c.
First, we will calculate the total energy consumed:
[tex]E = (0.5\ KW)(6\ h/d)(30\ d)\\E = 90\ KWh[/tex]
Now, for the cost:
[tex]Cost = (Unit\ Cost)(Energy)\\Cost = (\$ 0.08\KWh)(90\ KWh)[/tex]
Cost = $ 7.2
A 50 W light bulb is plugged into a standard
110 V outlet.
a) How much does it cost per month (31
days) to leave the light turned on? Assume
electric energy cost of 3.39 cents/kW · h.
Answer in units of dollars
b) What is the resistance of the bulb?
c) What is the current in the bulb?
Answer in units of mA
Answer:
$1.26
Explanation:
Power =energy/ time
energy =powerxtime
energy =50x31x24=37200
=37.2kwh
1kwh =3.39
37.2kwh=3.39x37.2=126.108cent
=$1.26
During the course of a demonstration the professor is called away. When he returns he finds a beaker of water that was at room temperature is now at a slightly higher temperature. There is a stirring rod on the desk and a cigarette lighter. The professor can assume that the temperature increase is due to either heat added or mechanical work done. mechanical work done on the system. heat added to the system.
Answer:
Either heat added or mechanical work done.
Explanation:
Since he found stirring rod on the desk and a cigarette lighter. This means that the beaker was probably either heated with the aid of fire from the lighter.
Also, the stirring rod could have been used to stir the water which will increase the kinetic energy which also means an increase in temperature.
Thus, it's either heat was added or mechanical work was done as a result of stirring.
Spring is a time when animals reproduce. What might you see a heron do? Build a nest A. Grow feathers A. Hibernate Migrate
Answer:
A. Build a nest.
Explanation:
It wont do any of the other things and they need a place to sleep and lay eggs plus it is a bird
The heron birds belong to Ardeidae family. Some of the species among them are referred to as egrets or bitterns rather than a heron. A heron bird build a nest during Spring. The correct option is A.
What is Heron bird?The heron is known as a long-legged, long-necked, fresh water and coastal birds. It a medium to large size bird with long necks and legs. They exhibit sexual dimorphism in size. The two male and female sex of the same species show distinct attributes beyond their difference in sexual organs.
Almost all the heron species are found in water and they are essentially non-swimming water birds which feed on the margins of lakes, ponds, sea, rivers and swamps. The small species of heron are generally referred to as the dwarf bittern.
The nesting season indicates the time of year during which birds build nests and lay eggs in them. In most cases bring up their young. It is in the spring season lot of food are available.
Thus the correct option is A.
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#SPJ3
Write a paragraph descibing three rides in an amusement park and how rides cause you
to move.
Answer:
Hope this helps! can I have brainliest im trying to level up.
Explanation:
Bumper cars are a great place to see Sir Isaac Newton’s three laws of motion in action. Here’s how:
Newton’s First Law: Every object in motion continues in motion and every object at rest continues to be at rest unless an outside force acts upon it.
This is because all objects have inertia – the property of matter that resists changes to the object’s motion.
Newton found that if a ball is sitting on a table, it will stay sitting there because that is what it ‘wants’ to do.
If the ball is set in motion, it will keep traveling in a straight path because, again, that is what it ‘wants’ to do.
An object in motion will not stop, slow down, or change its direction unless an outside force acts on it (such as gravity, friction, and air resistance).
When you are riding in a bumper car and end up in a collision with another bumper car, you feel a jolt. This is because your body’s inertia wants it to keep traveling in the direction it was moving with the car even though your bumper car has now suddenly stopped.
Newton’s Second Law: The greater the mass of an object, the harder it is to change its speed.
(More force is needed to move it.)
You already know this law and practice it in your everyday life. Something that is small, such as a pebble, is much easier to pick up and throw than something that is large and heavy, such as a boulder.
When riding in the bumper cars, you may have noticed that people who weigh less tend to get pushed around more than people who weigh more.
The more mass (weight) an object has, the more force it takes to move it.
And since all the bumper cars usually have the same top velocity, the cars carrying more mass will never travel as far as the cars carrying less mass after a collision.
Newton’s Third Law: For every action, there is an equal and opposite reaction.
If two bumper cars traveling at the same speed and carrying the same amount of weight run into each other, they will bounce off and move an equal distance away from each other.
And based on the second law, if there is a difference in the amount of weight being carried in the two cars, the car with less weight will travel farther away from the point of impact than the car carrying more weight.
At what rate is work done if the 250 Newton object from number six is moved into a hot at 4 m in four seconds
Answer:
250w
Explanation:
W=Fd
W= 250 x 4= 1000J
P=E/t=1000/4s=250w
Calculate the average speed of blood flow in the major arteries of the body, which have a total cross-section area of about 2.0cm^2.
Answer:
0.9m/s
?
Explanation:
A power plant burns coal to generate electricity. Suppose that 1000 J of heat (Q) from the coal fire enters a boiler, which is kept at a constant temperature of 900 C. That 1000 J is used to boil water in a boiler. The steam from the boiler is used to drive a turbine that creates electricity (work). The excess heat is put into a cooling tower at 5 C.
Carnot efficiency If everything is perfectly efficient,
• What is the maximum efficiency that the plant could operate at?
• How much work could be done starting from that 1000 J?
Answer:
The work done will be "763 J". A further explanation is given below.
Explanation:
The given values are:
[tex]Q_1=1000 \ J[/tex]
Temperature,
[tex]T_1=900^{\circ} C[/tex]
i.e,
[tex]=1173[/tex]
[tex]T_2=5^{\circ}C[/tex]
i.e.,
[tex]=278[/tex]
As we know,
⇒ [tex]\eta =1-\frac{T_2}{T_1}[/tex]
On substituting the values, we get
⇒ [tex]=1-\frac{278}{1173}[/tex]
⇒ [tex]=\frac{1173-278}{1173}[/tex]
⇒ [tex]=\frac{895}{1173}[/tex]
⇒ [tex]=0.763[/tex]
then,
⇒ [tex]W=\eta Q_1[/tex]
⇒ [tex]=0.763\times 1000[/tex]
⇒ [tex]=763 \ J[/tex]
II) Write meanings and frame sentences of the following words
1) loftily
2) dispute
3) diverged
4) jostle
5) souvenirs
6) coveted
Answer:
Explanation:
1. loftily - To do something in an arrogant manner.
He answered her in a loftily manner.
2) dispute - This is an argument or a disagreement.
There is a dispute between the friends.
3) diverged - To move in a different direction or separate from others.
The road diverged here to my town.
4) jostle - To come in contact, push, or collide with someone in a crowd .
The boy jostled his way through the crowd.
5) souvenirs - Something kept ad a reminder or taken as a memory of something or someone.
Before his dad died, he gave James his watch as a souvenir.
6) coveted - Something or someone that's greatly envied or desired.
James always covered power but didn't eventually get it.
What is the speed of an object moving around a 0.75 m radius circle that completes a revolution in 0.50 seconds?
Answer:
the speed of an object is 9.42 m/s
Explanation:
The computation of the speed of an object is given below:
v = 2πr ÷ t
where
v denotes the speed
r denotes the radius
r denotes the time
So,
= 2 × 3.14 × 0.75 ÷ 0.50
= 9.42 m/s
Hence, the speed of an object is 9.42 m/s
the same would be considered and relevant too
When U-238 transmutates into Th-234, this represents _______.
Alpha decay
Electron capture
Beta-decay
Gamma decay
Answer:
A: Alpha decay.
Explanation:
The transmutation of ²³⁸U is a nuclear reaction that yields ²³⁴Th and an alpha particle.
Now, Alpha decay is a radioactive decay whereby an atomic nucleus emits an alpha particle which then changes into an atom with a mass number that is decreased by four and atomic number decreased by 2.
In this case, mass number is reduced from 238 to 234. Thus, it's an alpha decay.
A+10 u charge and a -10 4C (1 HC - 106 C), at a distance of 0.3 m,
A. Repel each with a force of 10 N
B. Attract each other with a force of 10 N
C. Repel each other with a force of 20 N
D. Attract each other with a force of 20 N
If anyone knows what’s going on here please help
Answer:
B. Attract each other with a force of 10 newtons.
Explanation:
Statement is incorrectly written. The correct form is: A [tex]+10\,\mu C[/tex] charge and a [tex]-10\,\mu C[/tex] at a distance of 0.3 meters.
The two particles have charges opposite to each other, so they attract each other due to electrostatic force, described by Coulomb's Law, whose formula is described below:
[tex]F = \frac{\kappa \cdot |q_{A}|\cdot |q_{B}|}{r^{2}}[/tex] (1)
Where:
[tex]F[/tex] - Electrostatic force, in newtons.
[tex]\kappa[/tex] - Electrostatic constant, in newton-square meters per square coulomb.
[tex]|q_{A}|,|q_{B}|[/tex] - Magnitudes of electric charges, in coulombs.
[tex]r[/tex] - Distance between charges, in meters.
If we know that [tex]\kappa = 8.988\times 10^{9}\,\frac{N\cdot m^{2}}{C^{2}}[/tex], [tex]|q_{A}| = |q_{B}| = 10\times 10^{-6}\,C[/tex] and [tex]r = 0.3\,m[/tex], then the magnitude of the electrostatic force is:
[tex]F = \frac{\kappa \cdot |q_{A}|\cdot |q_{B}|}{r^{2}}[/tex]
[tex]F = 9.987\,N[/tex]
In consequence, correct answer is B.
What voltage indicates the voltmeter connected to the ends of a conductor, if the ammeter connected in series with this conductor indicates a current of 400 mA. The resistance of the conductor is equal to 5kΩ.
Explanation:
V= Current × Resistance
V= 400mA × 5kohms
V= 2000V
Which of the following is an example of a healthy behavior?
OA
Binge drinking of alcohol
OB.
Smoking cigarettes
OC.
Driving a car recklessly
OD.
None of the above
PE Not Physics
Answer moderate alcohol can be good for you health
Explanation: but I wouldn't do none of those things to be honest
SMARTEST
Answer:
none of the above
Explanation:
its an easy question haha
If a 75 W lightbulb is 15% efficient, how many joules of light energy does the bulb produce every minute?
Answer:
11.25J
Explanation:
15=(output/75)x100
output =(75x15)/100=11.25J
A chain is wrapped around pulley and pulled with a force of
16.0N .The pulley has a radius of 0.20 m. The pulley's rotational
speed increases from 0.0 to 17.0 rev/min in 5.00s What is the moment
of inertia of Pulley?
The moment of inertia of Pulley is 8.89 kgm².
Angular acceleration of the pulleyThe angular acceleration of the pulley is calculated as follows;
[tex]\alpha = \frac{\omega_f - \omega _i}{t}[/tex]
where;
ωi is the initial angular velocity = 0 ωf is the final angular velocity = 17 rev/mint is the time of motionFinal angular velocity in radian per second is calculated as
[tex]\omega _f = 17 \frac{rev}{\min} \times \frac{2\pi \ rad}{1 \ rev} \times \frac{1\min}{60 \ s} = 1.78 \ rad/s[/tex]
Now, solve for angular acceleration
[tex]\alpha = \frac{1.78-0}{5} \\\\\alpha = 0.36 \ rad/s^2[/tex]
Moment of inertia of the pulleyThe the moment of inertia of Pulley is determined using the formula for torque.
Iα = Fr
I = Fr/α
I = (16 x 0.2)/(0.36)
I = 8.89 kgm²
Thus, the moment of inertia of Pulley is 8.89 kgm².
Learn more about moment of inertia here: https://brainly.com/question/25803184
What is the difference between 1 celcius and 1 kelvin
Answer:
One degree unit on the Celcius scale is equivalent to one degree unit on the kelvin scale. The only difference between these two scales is the zero point. The zero point on the Celcius scale was defined as the freezing point of water, which means that there are higher and lower temperatures around it.
Calculate the amount, in grams, of an original 300 gram sample of potassium 40 remaining after 3.9 billion years.
a. 300
b. 150
c. 75
d. 37.5
a car initially at rest move with the constant accerates along straght line read after it's spread increase and finally related uniformly. the time interval for the three parts of the jounry are in the ratio 1:3:1 find average velocity ?
Answer:
32km per hour
Explanation:
Explanation:
In first case v = a t
==> a t = 40 km p h
Now distance covered S1 + S2 + S3
S1 = 1/2 a t^2 and S3 = 1/2 a t^2
But S2 = 3t * 40 = 120 t km
Hence total distance = at^2 + 120 t
Time taken (total) = t + 3t + t = 5 t
Hence average speed = at^2 + 120 t / 5 t
Cancelling t we have at + 120 / 5 = 40 + 120 / 5 = 160/5 = 32 km per hour
Compare and contrast the strength of the forces between two objects with a mass of 1 kg each, a charge of 10
and at a distance of 1 m from each other.
Answer:
Let's see the similarities between the two forces
* are proportional to the product of a magnitude, mass or charge
* They are inversely proportional to the square of the distance
* They are long-range forces since zero is not made up to an infinite distance. The gravitational force is always attractive, the electrical force can be attractive or repulsive.
The differences in them
* The electric force in much greater than the gravitational force
* The gravitational force is always attractive, the electrical force can be attractive or repulsive.
Explanation:
Let's start by calculating each force.
Gravitational force
F =[tex]G \frac{m_1m_2}{r^2}[/tex]
let's calculate
F = 6.67 10⁻¹¹ 1 1 / 1²
F = 6.67 10⁻¹¹ N
Electric force
F = [tex]k \frac{q_1q_2}{r^2}[/tex]
indicates that the charge is q = 10 C
F = 9 10⁹ 10 10 / 1²
F = 9 10¹¹ N
Let's see the similarities between the two forces
* are proportional to the product of a magnitude, mass or charge
* They are inversely proportional to the square of the distance
* They are long-range forces since zero is not made up to an infinite distance. The gravitational force is always attractive, the electrical force can be attractive or repulsive.
The differences in them
* The electric force in much greater than the gravitational force
* The gravitational force is always attractive, the electrical force can be attractive or repulsive.
4. A car is moving at 10m/s when it begins to accelerate to 2.5m/s. (a). How
long does it take to reach a 25m/s?
62.5 m/s
Explanation:
A sound wave travels with a velocity of 330 m/s and has a frequency of 500 Hz. What is its
wavelength?
Answer:
Wavelength = 0.66 meters
Explanation:
Given the following data;
Speed = 330 m/s
Frequency = 500 Hz
To find the wavelength;
Mathematically, wavelength is calculated using this formula;
[tex] Wavelength = \frac {speed}{frequency} [/tex]
Substituting into the equation, we have;
[tex] Wavelength = \frac {330}{500} [/tex]
Wavelength = 0.66 meters
Visible light falls into wavelength ranges of 400-700 nm, for which 1 m = 1 × 10 9 nm . The energy and wavelength of light are related by the equation E = h c λ where E is energy in Joules, h is Planck's constant ( 6.626 × 10 − 34 J-s ), c is the speed of light ( 2.998 × 10 8 m/s ), and λ is the wavelength in m. If a visible light photon has a wavelength of 560.6 nm, what is the energy of the photon (in J)?
Given the wavelength of the visible light photon, the energy of the photon is 3.54 × 10⁻¹⁹J
Given the data in the question;
Wavelength of visible light; [tex]\lambda = 560.6 nm = 5.606*10^{-7}m[/tex]
Speed of light; [tex]c = 2.998 * 10^8 m/s[/tex]
Planck's constant; [tex]h = 6.626 * 10^{-34} J.s[/tex]
The energy and wavelength of light are related by the equation:
[tex]E = \frac{hc}{\lambda}[/tex]
Where E is energy of photon in Joules, h is Planck's constant, c is the speed of light and λ is the wavelength,
We substitute our given value into the equation
[tex]E = \frac{(6.626*10^{-34}J.s)(2.998*10^8m/s)}{5.606*10^{-7}m} \\\\E = \frac{(1.986*10^{-25}J.m}{5.606*10^{-7}m}\\\\E = 3.54 * 10^{-19}J[/tex]
Therefore, given the wavelength of the visible light photon, the energy of the photon is 3.54 × 10⁻¹⁹J
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A satellite orbiting Earth at a velocity of 3700 m/s collides with a piece of
space debris traveling at 5000 m/s. If the objects have the same mass and
the space debris has a velocity after collision of 3700 m/s, what is the
velocity of the satellite after the collision?
Answer:
Explanation:
they trade velocities... so the Satellite now is going 5000 m/s
The energy of motion is called...?
A flag is waved 3.2 m above the surface of a flat pool of water. When viewed from under the water, what is the magnification of the flag? Let the indices of refraction nwater = 1.33 and nair = 1.00.
1.33
0.754
1
1.67
Answer:
1.33
Explanation:
For an optical instrument, the magnification ratio of the apparent diameter of the image to that of the object.
Mathematically, from the given information;
Magnification[tex]= \dfrac{n_{water}}{n_{air}}[/tex]
where;
[tex]n_{water} =1.33\\ \\ n_{air} = 1.00[/tex]
[tex]= \dfrac{1.33}{1.00} \\ \\= \mathbf{1.33}[/tex]
What are three hazardous chemicals found in cigarette smoke?
Answer: I believe hydrogen cyanide, carbon monoxide, and ammonia are the three chemicals involved, but im not sure
how does increasing energy affect the amplitude of a wave?
Answer:
The amount of energy carried by a wave is related to the amplitude of the wave
Explanation:
A high energy wave is characterized by a high amplitude; a low energy wave is characterized by a low amplitude. The energy imparted to a pulse will only affect the amplitude of that pulse.
Hope this helped!!!
Explain What's make up macromolecules?
Answer:
Atoms
Explanation:
Atoms make up everything
After landing on an unfamiliar planet, a space explorer constructs a simple pendulum of length 54.0 cm. The explorer finds that the pendulum completes 98.0 full swing cycles in a time of 135s.
Required:
What is the value of g on this planet?
Answer:
g = 11.2 m/s²
Explanation:
First, we will calculate the time period of the pendulum:
[tex]T = \frac{t}{n}[/tex]
where,
T = Time period = ?
t = time taken = 135 s
n = no. of swings in given time = 98
Therefore,
[tex]T = \frac{135\ s}{98}[/tex]
T = 1.38 s
Now, we utilize the second formula for the time period of the simple pendulum, given as follows:
[tex]T = 2\pi \sqrt{\frac{l}{g}}[/tex]
where,
l = length of pendulum = 54 cm = 0.54 m
g = acceleration due to gravity on the planet = ?
Therefore,
[tex](1.38\ s)^2 = 4\pi^2(\frac{0.54\ m}{g} )\\\\g = \frac{4\pi^2(0.54\ m)}{(1.38\ s)^2}[/tex]
g = 11.2 m/s²
Someone please help and I will mark you as Brainlist! No
2) Translation kinetic energy is defined as the energy of a system due to the motion of the system’s...
• center of mass
• axis of symmetry
• molecules
• rotational movement
3) the work- energy theorem states that
• when work is done on a system, no energy changes can occur.
• when work is done on a system, a change in energy occurs.
• when energy is released by a system, work can be done.
• when work is done by a system, energy is released
Answer:
2) center mass
3) when work is done by a system, energy is released
Explanation: