Answer:
7.22 m³ of water should be stored behind the hydroelectric dam.
Explanation:
First we find the total energy that can be stored in the battery. For that purpose we use the formula:
P = VI
where,
P = Power delivered by battery
V = Voltage of Battery = 12 volts
I = Current in Battery
Multiplying both sides by time interval (t), we get:
Pt = VIt
where,
Pt = (Power)(Time) = Total Energy Stored in Battery = E = ?
It = Current Rating of Battery = (50 A.min)(60 s/min) = 3000 A.s
Therefore,
E = (12 volt)(3000 A.s)
E = 36000 J
Now, we have to find the energy required to fully charge the battery:
Energy Required = ΔE = Total Energy Capacity(E) - Already Stored Energy
ΔE = 36000 J - 600 J
ΔE = 35400 J
Now, this energy must be equal to the potential energy of water stored behind hydroelectric dam to fully charge the battery, provided that the conversion efficiency is 100 %.
Therefore,
ΔE = mgh
where,
m = mass of water behind hydroelectric dam
g = 9.8 m/s²
h = height of dam = 50 cm = 0.5 m
Therefore,
35400 J = m(9.8 m/s²)(0.5 m)
m = (35400 J)/(4.9 m²/s²)
m = 7224.5 kg
Now, to find the volume of stored water, we use:
ρ = m/V
V = m/ρ
where,
ρ = density of water = 1000 kg/m³
V = Volume of water behind dam = ?
V = (7224.5 kg)/(1000 kg/m³)
V = 7.22 m³
Imagine that you have a 500 g iron pot (c = 0.440), a 500 g copper pot (c = 0.385), and a 500 g aluminum pot (c = 0.897). You fill each pot with 250 mL of water and heat the water to 100°C on a stove. Which pot will keep the water warm the longest? Explain your answer.
Answer:
Aluminium
Explanation:
If we calculate the heat transfer for all the substances, we have
Mc(∆T)
Where M is mass
C is heat capacity
∆T is temperature change.
For iron
Mc(∆T) = 500 ×0.440×100= 22000J
For copper
Mc(∆T) = 500 ×0.385×100= 19250J
For aluminium
Mc(∆T) = 500 ×0.897×100= 44850J
Aluminium has the highest heat capacity and would take longest for this heat capacity to be dissipated under similar condition.
when scientists publish experimental results their results are often criticized by other scientists how is this process a source of strength of Science? It encourages scientists to give convincing evidence for the results
it allows scientists to keep their data secret
a scientific model is not used full unless everyone thinks it's true
or if forces scientists to publish results that are in line with current theories
Answer: It encourages scientists to give convincing evidence for the results
Answer:
A.) would be the right answer
Explanation:
I took the test :)
I beggggg youu to solve this for me, I'm giving you 60 POINTS !!!
please solve it on a paper and send it i should submit it tomorrow it's graded
Answer:
but where is the question ?
Explanation:
hope it works out
Answer:
where the question about?
Explanation:
I think the question is invisible
Suggest what would happen to the pressure of a gas at constant temperature if the volume of the gas is halved.
Answer:
8.31 m3-Pa/mol-K
Explanation:
a diode can be used as a rectifier. what is the function of a rectifier?
Explanation:
Rectifier diodes are used in power supplies to convert alternating current (AC) to direct current (DC), a process called rectification. They are also used elsewhere in circuits where a large current must pass through the diode.
In a hydroelectric power station, how much potential energy is lost by 100tonnes of water flowing down through the pipes, falling a vertical distance of 200metres? [1tonne=1000kg.]
Answer:
196000000 J
Explanation:
Potential Energy: This can be defined as the energy of a body due to its position in the gravitational field.
From the question,
P.E = mgh.................. Equation 1
Where P.E = potential Energy, m = mass of the water, h = height, g = acceleration due to gravity.
Given: m = 100 tonnes = (100×1000) = 100000 kg, h = 200 m
Constant: g = 9.8 m/s²
Substitute into equation 1
P.E = 100000(200)(9.8)
P.E = 196000000 J.
Note: When a object falls through a height he losses its potential energy.
Hence the potential energy lost = 196000000 J = 196 MJ.
if a rock has a speed of 12 m/s as it hits the ground, from what height did it fall assuming the speed was zero.its mass is 50 kg
Answer:
a=9.8 ms−2 12^2=0^2+2×9.8×H
H=7.35m
Explanation:
To find the height the following formula should be used: v2=u2+2aH
Assuming this occurs on earth,
Answer:
7.3 m
Explanation:
The mass of a certain man is 250g..
I. What is the weight of the man on earth
ii. What is the weight of the man on the moon
I promise to mark u the brainliest, please help me
Answer:
2,450
400
Explanation:
Pls brainliest me
What are some advantages
and disadvantages to using
superconductors as electric
transmission lines
Answer:
Insulators show very high resistance to electricity. Conductors like copper show some resistance. Another class of materials show no resistance at all when cooled to very low temperatures, cooler than the coolest deep freezer. Called superconductors, they were discovered in 1911.
Explanation: i looked it up
What is the symbol for Pressure ? Help
Answer:
The answer is Pascal or Pa.
Answer:
Pa or small p
Explanation:
Force over Area. The SI unit is Pascal
an ice cube of density 0.9g/cm3floats in fresh water of density 1g/cm³ what fraction of volume of ice is submerged?
Answer:
9/10
Explanation:
From Archimedes' principle, the buoyant force on the ice equals the weight of water displaced. Since the buoyant force equals the weight of the ice. then
ρ₁V₁g = ρ₂V₂g where ρ₁ = density of ice = 0.9 g/cm³ and V₁ = volume of ice and ρ₂ = density of water = 1 g/cm³ and V₂ = volume of water.
So. ρ₁V₁ = ρ₂V₂
V₁ = ρ₂V₂/ρ₁
= 1 g/cm³V₂/0.9 g/cm³ = 10V₂/9
Now, let x be the fraction of volume of ice submerged. So V = xV₁ = volume submerged. This volume also equals the volume of water since the submerged ice displaces its own volume of water.
So V = V₂
xV₁ = V₂
x(10V₂/9) = V₂
10x/9 = 1
x = 9/10
what is the capital of Ghana and also Togo.
Answer:Ghana - Accra Togo - Lomé I hope this helps mark me brainlist
Explanation:
Accra is the Capital of Ghana
Accra was founded in the 17th century by the Ga people. It became the capital of the British Gold Coast in 1877 and the capital of Ghana on the formation of the country as an independent state in 1957
Accra Is the Second Most Expensive City in Africa
Accra is known for its colorful textile and used or second-hand clothing markets. Located inside the Makola Market, Kantamanto is the largest trading point in all of Accra.
The capital of Togo is Lomé
Lomé, city, capital of Togo. Lomé lies on the Gulf of Guinea (Atlantic coast) in the extreme southwestern corner of the country. Selected as the colonial capital of German Togoland in 1897, it became important as an administrative, commercial, and transport centre.
It is also the country's chief port, from where it exports coffee, cocoa, copra, and oil palm kernels- Lome
Lomé was founded by the Ewe, an indigenous ethnic group, in 1880. Located on the southwestern Atlantic coast of Togo, Lomé has a long history of trade. In 2000, an estimated 900,000 people resided in Lomé. Europe's “Scramble for Africa” began in 1880.
can there be shadows at night outside?
Answer:
To see a shadow there most be light provided, even if it's night and there are lights, we can still see the shadow but if there is no light, we can't.
Hope it helped (:
Answer: yes of course, but there should be some light to make or see shadows.
How many meters is in 32 km
Answer:
32000 m
Explanation:
1000m in 1 km, so 32000m in 32 km.
Answer:
32000m
Explanation:
1km=1000m
so 32 kn is equals to 32000m
iv. The lift raises a car of mass 850 kg to a height of 2.1 m. It uses a force of 8330 N and takes 4 seconds to raise the car. What is the power of the lift? (1 point)
Answer:
Power is 4373.25 W
Explanation:
We have,
The lift raises a car of mass 850 kg to a height of 2.1 m. It uses a force of 8330 N and takes 4 seconds to raise the car. It is required to find the power of the lift. Power is equal to the rate at which the work is done. So,
[tex]P=\dfrac{Fd}{t}\\\\P=\dfrac{8330\times 2.1}{4}\\\\P=4373.25\ W[/tex]
So, the power of the lift is 4373.25 W.
would iron and carbon from metallic bonds
Answer:
NO
Explanation:
Since iron is a metal and carbon is a non- metal, they cannot form a metallic bond.
What is the magnitude of impulse of a 2.7 gram ping pong ball initially moving at 15 m/s, if hit by a ping pong paddle and then moves the opposite direction at 14/ms
Answer:
impulse = 0.0783 kg.m/s
Explanation:
The impulse is the product of the force and an interval of time. This can be represented in terms of the mass of the body and the change in the velocity of the body in such a time:
[tex]F\Delta t=m\Delta v[/tex] [tex]=|m(v_f-v_i)|[/tex]
m: mass of the body = 2.7gm = 0.0027 kg
vf: final velocity = -14m/s
vi: initial velocity = 15m/s
vf is negative because the direction of the ball is opposite to the initial direction:
[tex]|m(v_f-v_i)|=|(0.0027kg)(-14m/s-15m/s)|=0.0783\frac{kg.m}{s}[/tex]
hence, the impulse of the ping pong ball is 0.0783 kg.m/s
Please answer these: Q1. i. In what two ways combustion can be useful to us? Explain by giving examples. ii. Explain why decomposition of sugar on heating is an irreversible change. Q2. In order to answer this question you need to look around your immediate surroundings to find examples of rusting of iron or any other metal. i. What makes iron rust? ii. Why is the rusting of iron a problem? Give any 3 examples from daily life where rusting has been a disadvantage. iii. Suggest any two ways that can help prevent rusting of iron. Q3. i. Give two differences between a physical change and a chemical change. ii. Explain whether condensation of water vapour is a physical or a chemical change. iii. Write word equations for the following reactions: a. Breaking down/ electrolysis of water b. synthesis of water c. decomposition of sugar d. photosynthesis in plants
Answer:
1) combustion can be used as a source of energy.
Combustion is used to power rockets
ii) Decomposition of sugar is a chemical change and new substances are formed.
2)corrosion of pipes
Corrosion of bridges
Corrosion of knives and blades at home
I) iron rusts due to the action of air and moisture bon the metal setting up an electrochemical process in which the iron is the anode. This leads to the corrosion of the iron metal.
ii) Rusting is a problem because it reduces the economic value of iron. Rust weakens iron and threatens the integrity of materials made from iron.
Iron rusting may lead to the collapse of a bridge
Iron rusting makes a blade blunt
Iron rusting weakens pipes made of iron
iii) Rusting of iron can be prevented by galvanizing the iron or by painting the iron.
3) chemical change leads to the formation of a new substance while physical change does not lead to the formation of a new substance.
Chemical changes are not easily reversible while physical changes are easily reversible.
ii)condensation of water vapour is a physical change
iii)
Electrolysis of water;
Two moles of water---> two moles of hydrogen gas + one mole of oxygen gas
Synthesis of water;
two moles of hydrogen gas + one mole of oxygen gas---->Two moles of water
Decomposition of sugar;
One mole of Sucrose---> twelve moles of carbon + eleven moles of water + heat
Six moles of carbon dioxide + six moles of water +energy------> one mole of sugar + six moles of oxygen
Explanation:
Combustion is useful as a source of energy because it is used in power generation. Currently, combustion is being used to power rockets. It is also used as a way of providing heat at home.
One of the characteristics of a chemical change is that it leads to the formation of new substances. Since the decomposition of sugar leads to the formation of carbon and water, it is an irreversible chemical change.
When water is heated, it is converted into vapour which can settle on a surface and convert back to liquid water. This is a physical change.
n resistance is each of resistance R is first connected in series and then in parallel what is the ratio of series and parallel combination
Answer:
The ratio of the ratio of series and parallel combination is n²:1.
Explanation:
The equivalent resistance in case of series combination is given by :
[tex]R_s=R_1+R_2+.....+R_n=nR[/tex] ....(1)
The equivalent resistance in case of parallel combination is given by :
[tex]R_P=\dfrac{1}{R_1}+\dfrac{1}{R_2}+.....+\dfrac{1}{R_n}=\dfrac{R}{n}[/tex] ....(2)
Dividing equation (1) and (2) we get :
[tex]\dfrac{R_s}{R_P}=\dfrac{nR}{R/n}\\\\\dfrac{R_s}{R_P}=\dfrac{n^2}{1}\\\\R_s:R_P=n^2:1[/tex]
So, the ratio of the ratio of series and parallel combination is n²:1. Hence, this is the required solution.
n resistance is each of resistance R is first connected in series and then in parallel , the ratio of series and parallel combination will be [tex]n^{2}[/tex] : 1
In a series combination, the resistances are connected with end to end in contact, such that current flow is equal in all the resistances in the combination. Whereas in the parallel combination, resistances are connected in such a manner that they get an equal voltage across their ends.
Parallel combination. When two or more resistances are connected between the same two points, they are said to be connected in parallel combination. The reciprocal of the combined resistance of a number of resistances connected in parallel is equal to the sum of the reciprocals of all the individual resistances.
if n number of resistances are connected in series combination .
R (equivalent ) = R1 + R2 + R3 + R4 -------- + Rn
= R + R + R + R ---------------- + R
= n*R
if n number of resistances are connected in parallel combination .
1/ R (equivalent ) = 1/R1 + 1/R2 + 1/R3 ---------------- 1/Rn
= 1/R + 1/R + 1/R + --------------------- 1/R
= n/R
R (equivalent ) = R/n
Ration = series combination / parallel combination
= n*R / (R/n) = [tex]n^{2}[/tex] /1
= [tex]n^{2}[/tex] : 1
To learn more about parallel combination here
https://brainly.com/question/15048645
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What do nuclear fission and nuclear fusion have in common?
A. They start with the same reactants.
B. They're both used in power plants.
C. Their products have more mass than their reactants.
D. Their products have less mass than their reactants.
Answer:
B
Explanation:
Fission and Fission are nuclear reaction processes that releases energy.
Fission is the process where the nuclei of an atom splits into smaller nuclei of same element or elements of smaller nuclei when Fussion is when two smaller nuclei combined to form one of a different element of a higher nuclei. These processes release energy.
Answer:
D. Their products have less mass than their reactants.
Explanation:
When did Pangaea begin to break apart?
Answer:
Hey!
Well according to scientific data and analysis, it started to break up about 175 - 200 million years ago!!
Explanation:
HOPE THIS HELPS!!
Answer:
250 million (:
Explanation:
If a body of mass 10 kg is pushed with a force of 15N, then the acceleration of the body is
Answer:
1.5m/s2
Explanation:
F=ma
a=F/m
a=15/10
a=1.5m/s2
WILL GIVE BRAINLIEST AND 10 POINTS!! An asteroid is hustling through the solar system, in the vicinity of the inner planets. Based on what you know about gravitational attraction, which planet is LEAST likely to attract the asteroid?
Answer:
mercury
Explanation:
The planet with the smallest mass must have the smallest gravitational pull - which is mercury, with a pull of approx. 0.38 times the Earth's gravitational pull.
Explain the following behaviour of molecules water rises up in a harrow tubes but mercury which is also a liquid falls in a narrow tubes to level below the outside surface
Answer: find the answer in the explanation
Explanation:
The capillarity of water molecules is different from the mercury molecules.
What is capillarity ?
This is the tendency of a liquid substance to rise in a capillary tube.
Molecules water rises up in a harrow tubes because of the force of adhesion between the water molecules and the tube molecules is greater than the force of cohesion between the water molecules. This helps water to wet the tube and rise. While mercury which is also a liquid falls in a narrow tubes to level below the outside surface because the force of cohesion between the mercury molecules is greater than the force of adhesion between the mercury molecules and the tube molecules. Mercury does not wet.
Earth is a dynamic system what exactly does this mean
Answer:
The answer to the following question is given below.
Explanation:
This means a mixture of interconnected, interlinked, or interactive elements that establish the collaborative entity or entities.
The Earth system manages to maintain its very presence on even a macro level as well as processes in general thru the engagement of all its elements. This affects such as erosion, whereas others happen unexpectedly, such as an earthquake. It is crucial to keep our lifestyle in mind that we can recognize all such adjustments as well as their implications.What does the phrase "1 meter per second per second" means? A. The velocity of an object can increase by 1 meter per second, for every minute of time measured. B. The velocity of an object can increase by 1 meter per second, for every second of time measured. C. The velocity of an object can increase by 1 meter per second.
Explanation:
"1 meter per second per second" means acceleration of an object. It is equal to the rate of change of velocity. Its SI unit is [tex]m/s^2[/tex].
It is simply given by :
[tex]a=\dfrac{dv}{dt}[/tex]
dv is change in velocity
dt is small interval of time
"1 meter per second per second" means that the velocity of an object can increase by 1 meter per second.
HELLO.
Hope you are having a nice morning/day/night. PLEASE HELP.
Explain why water storage tanks in houses are erected as high as possible
Answer:
Hello! Thanks! I hope you are too! hope this helps!
Explanation:
The primary reason is to create more water pressure. ... If a municipal water tank is elevated to more than a hundred feet above the ground, there is an increase of . 43 psi per foot. A tank that has been elevated to an appropriate height can create water pressure similar to that created by a large pump
Answer:
✌✌✌✌✌✌✌✌✌✌✌
Explanation:
The primary reason is to create more water pressure. ... If a municipal water tank is elevated to more than a hundred feet above the ground, there is an increase of . 43 psi per foot. A tank that has been elevated to an appropriate height can create water pressure similar to that created by a large pump.
QUICK WILL MARK BRAINLIEST
As light shines from air to water, the index of refraction is 1.02 and the angle of
incidence is 38.0 °. What is the light's angle of refraction?
29.8°
32.5°
37.1°
39.8°
Answer:
37.1°
Explanation:
The pressure exerted by 15m of liquid is 1500pa.The acceleration due to gravity g=10m/s^2.Calculate the density liquid.
Answer:
1500 divided by 150(15m x 10m/s^2) = 10
The power of a machine is 6000 W. This machine is scheduled for design improvements. Engineers have reduced the
time for the output by one half from 15 s to 7.5 s. What work would be required to cut the time in half.
Step #1
Step #2
Step #3
Explanation:
Work = power × time
W = (6000 W) (7.5 s)
W = 45,000 J