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Related Questions
Warm air is less dense than cold air. The same is true of water. You decide to take a bath and turn on both the hot and cold faucets. When the tub is one-third full, you dip your hand in and discover the water is too cold. You turn the cold water faucet off and keep the hot water turned on. You leave the hot water running for ten minutes. When you return and dip your hand in, you discover that the water in the tub is different temperatures in different places. It is too hot close to the faucet and in a top layer across the entire tub. When you sit down, however, the water in the bottom of the tub is cold. Explain how this happens and why: • how the hot water ended up in a layer on the top and near the faucet. • why this is or is not a transfer of heat. • how the temperature of the water in the tub will change over time. • why you will eventually want to get out of the tub, considering the air and your porcelain enameled steel tub.
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Answer:
Given that the warm water is less dense than the cold water, we have;
The cold water which is more dense than the warm water will remain settled in the lower part of the tub while particles of the less dense warm water will move above the cold water not being able to penetrate lower due of difference in their gravitational potential energiesThis is a case of (lack of) heat transfer due to inability of heat to penetrate into the lower layers and transfer the heat by conduction, from particle to particle, and therefore, one layer, the top remains warm while the other layer, the lower layer, remains coldWith time (over an hour) more and more warm water units will be able to penetrate deeper and make the lower layer warmer while the warm water at the top loses heat by evaporation to the atmosphere, until the entire water reaches equilibriumHeat will continue to be lost by evaporation to the air and by conduction through the porcelain to the steel tub until the water in the tub becomes coldExplanation:
Which of these describes a real image?
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I have no idea but this is my best guess as a sophomore in college
What is the normal force and gravitational force on a 55 kg person standing stationary?
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Answer:
539.55 N for both
Explanation:
F=ma
Mass is given at 55kg
And when finding gravitational force gravity's constant is an acceleration of 9.81m/s
F=(55)(9.81)
F= 539.55 N (for both)
Normal force cancels out gravitational force that's why we don't fall throught the floor.
We push down on the floor due to gravitational force but normal force keeps us upright pushing an equal amount back.
A football player kicks a football in a field goal attempt. When the football reaches its maximum height, what is the relationship between the direction of the velocity and acceleration vectors
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Answer:
The correct answer is - At the maximum height, the velocity and acceleration vectors are perpendicular to each other.
Explanation:
When the football reaches maximum height, then the vertical component of velocity will be zero and therefore the only component of velocity left will be the horizontal component, and acceleration of the object will be downward, due to gravity.
So at the maximum height, there is horizontal velocity only which means velocity is horizontal and acceleration is vertical thus, the velocity and acceleration are perpendicular to each other.
How much larger is the diameter of Jupiter compared to the diameter of Saturn?
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Electronic flash units for camera contain a capacitor for storing the energy used to produce the flash. In one such unit, the flash lasts for 1675s with an average light power output of 2.70 x 105 W . (a) If the conversion of electric energy to light is 95% efficient ( the rest of the energy goes to thermal energy), how much energy must be stored in the capacitor for one flash
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Answer:
420J
Explanation:
Power is the time rate of change in energy. Power is the ratio of energy to time. The S.I unit of power is in watts.
Given that the flash lasts for 1/675 s, power output is 2.7 * 10⁵ W. Hence:
Power = Energy / time
Substituting:
2.7 * 10⁵ W = Energy / (1/675)
Energy = 2.7 * 10⁵ W * 1/675 = 400J
Therefore the energy emitted as light is 400J.
Since the conversion of electric energy to light is 95% efficient, hence the energy stored as electrical energy is:
Energy(capacitor) = 5% of 400J + 400J = 0.05*400 + 400
Energy(capacitor) = 420J
a box of mass 4kg slides on the horizontal surface with kinetic frictional force of 8N. what coefficient of friction between the box and horizontal surface
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Answer:
ų=0.8
Explanation:
F=mg
F=4×9.81=39.24N
Ff=Fn-F
=39.24-8=31.24
ų=Ff÷Fn
=31.24÷39.24
=0.8
If a positively charged rod is brought near the knob of a positively charged electroscope, the leaves of the electroscope will...
A) converge, only
B) diverge, only
C) first diverge, then converge
D) first converge, then diverge
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Answer:
B
Explanation:
if a positively charged rod is brought near the knob of a neutral electroscope, it will attract some electrons up from the leaves onto the knob. That process causes both of the leaves to be positively charged (excess protons), and the leaves will diverge.
Plz I need help with this work
sheet
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Answer:
do it your self
Explanation:
on a proton is 1.6×10`¹⁹. how many protons are in one coulomb of charge
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Answer: There are [tex]6.25 \times 10^{18}[/tex] protons present in one coulomb of charge.
Explanation:
Given: Charge on proton = [tex]1.6 \times 10^{-19} C[/tex]
It is known that the charge on a proton is equal to the charge present on an electron.
Formula used to calculate number of protons is as follows.
Q = ne
where,
Q = charge considered
n = number of protons
e = charge on electron or proton
Substitute the values into above formula as follows.
[tex]Q = ne\\1 C = n \times 1.6 \times 10^{-19} C\\n = 0.625 \times 10^{19}\\= 6.25 \times 10^{18}[/tex]
Thus, we can conclude that there are [tex]6.25 \times 10^{18}[/tex] protons present in one coulomb of charge.
As shown in the diagram below, a 1 kg rock tied to a rope is
swung by a boy. This rock has a constant speed of 5 m/s,
and the length of the rope is 1 m. The rock's angular
momentum is
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Answer:
Explanation:
Angular momentum has a formula of L = mvr. Fillingin:
L = (1.0)(5.0)(1.0)
L = 5.0 kg*m/s
Electrical current is the flow of ____________
A) helium
B) protons
C) atoms
D) electrons
How much voltage is required to make 0.56 A flow through a 72-ohm resistance? [V = I x R]
A)48 V
B)36 V
C)40 V
D)52 V
WILL GIVE BRAINLIEST!!!
Answers
Solution :
A) Electric current is the flow of electrons .
B) We know, by ohm's law :
V = I × R
Putting given values in above equation, we get :
V = 0.56 × 72 V
V = 40.32 V
Hence, this is the required solution.
Suppose that scientists observe violent gas eruptions on a planet with an acceleration due to gravity of 3.9 m/s2. The jets throw sand and dust about 75 m above the surface. What is the speed i of the material just as it leaves the surface?
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Answer:
The velocity with which the sand throw is 24.2 m/s.
Explanation:
acceleration due to gravity, a = 3.9 m/s2
height, h = 75 m
final velocity, v = 0
Let the initial velocity at the time of throw is u.
Use third equation of motion
[tex]v^{2} = u^{2} - 2 g h \\\\0 = u^{2} -2\times 3.9\times 75\\\\u=24.2m/s[/tex]
The velocity with which the sand throw is 24.2 m/s.
?????? ?????help please
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Mark was traveling at 40 mph on a road with a drag factor of 0.85. His brakes were working at B0o/o efficiency. To the nearest tenth of a foot, what would you expect the average length of the skid marks to be if he applied his brakes in order to come to an immediate stop
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The average length of the skid marks to be if he applied his brakes in order to come to an immediate stop is 78.43 ft.
The given parameters:
Speed of Mark, v = 40 mphDrag factor, F = 0.85Working efficiency of the brake, n = 80%The average length of the skid marks to be if he applied his brakes in order to come to an immediate stop is calculated as follows;
[tex]v = \sqrt{30 D fn} \\\\40 = \sqrt{30 \times D \times 0.85 \times 0.8} \\\\40 = \sqrt{20.4 D} \\\\40^2 = 20.4D\\\\1600 = 20.4 D\\\\D = \frac{1600}{20.4} \\\\D = 78.43 \ ft[/tex]
Thus, the average length of the skid marks to be if he applied his brakes in order to come to an immediate stop is 78.43 ft.
Learn more about length of a skid mark here: https://brainly.com/question/16914218
The ratio of the number of pigs to the number of horse in a farm is 2 to 3 (2:3), if therected are 24 horses, what is the number of pigs?
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Answer:
16 pigs
Explanation:
Let the horses be H.
Let the pigs be P
Let the total number of animals be x.
Given the following data;
Ratio of P to H = 2:3 = 2 + 3 = 5
Number of horses = 24
To find the number of pigs;
First of all, we would determine the total number of animals x.
From the ratio of horse, H:
3/5 * x = 24
Cross-multiplying, we have;
3x = 120
x = 120/3 = 40
Next, we find the number of pigs;
Pigs = 2/5 * 40
Pigs = 80/5 = 16 pigs
A truck starts from rest with an acceleration of 0.3 m/ S^2 find its speed in km/h when it has moves through 150 m
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Answer:
9.5 m/s
Explanation:
Distance, S = 150m
Acceleration, a = 0.3 m/s^2
Initial velocity, u = 0 m/s
Final velocity, v
Use kinematics equation
v^2 - u^2 = 2aS
v^2 - 0 = 2*0.3*150 = 90
v = sqrt(90) = 9.49 m/s
How high can a body vertically thrown with a speed of 40m/s raise after 3 sec (neglecting air
resistance)
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y = 75.9 m
Explanation:
y = -(1/2)gt^2 + v0yt + y0
If we put the origin of our coordinate system at the point where a body is launched, then y0 = 0.
y = -(1/2)(9.8 m/s^2)(3 s)^2 + (40 m/s)(3 s)
= -44.1 m + 120 m
= 75.9
‘The Universe is expanding.’ Justify this statement with the Big bang model of universe and Hubble’s Law.
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Explanation:
The expansion of the universe is the increase in distance between any two given ... Metric expansion is a key feature of Big Bang cosmology, is modeled mathematically with the ...
A disk initially rotates counterclockwise at 1.0 rad.S but has a counterclockwise angular acceleration of 0.50rad/s^2 for 2.0s after this acceleration the disk is at an angle of 6.0 what us the disk angular position when the acceleration started
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Answer:
Explanation:
initial angular velocity is ω₀ = 1 rad /s
angular acceleration α = - 0.5 rad /s²
time t = 2 s.
Let the initial angular position be θ .
angular displacement = 6 - θ . rad .
angular displacement = ω₀ t - 1/2 α t²
6 - θ = 1 x 2 - 0.5 x 0.5 x 2²
6 - θ = 2 - 0.5 x 0.5 x 2²
= 2 - 1 = 1
θ = 6 - 1 = 5
5 rad is the answer.
what is the difference between mechanical advantage and distance advantage?
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the father sake to his daughter am happy with you change into reported speech
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Answer:
I am happy with you the father said to his daughter
Which of the following measurements has three significant figures
a. 0.0293 kg
b. 0.94 A
c. 5.321 V
d. 10.42 m
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Answer:
b. 0.94 i think is the answer
1. I get so much energy when I eat candy! What type of energy is this statement referring to?
O mechanical
O kinetic
O potential
O chemical
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The answer is chemical
A truck covers 40 km with an average speed of 80km/h. Then it travels another 40 km with an average speed of 40 km/h. The average speed of the truck for the total distanced covered is:
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Answer:
Average speed = 53.33 km/h
Explanation:
Below is the calculation for the average speed:
Given the average speed of for first 40 km = 80km/h
Time taken to cover the first 40 km = Total Distance / average speed
Time taken to cover the first 40 km = 40 / 80 = 0.5 hours
Given the average speed of for next 40 km = 40km/h
Time taken to cover the next 40 km = Total Distance / average speed
Time taken to cover the next 40 km = 40 / 40 = 1 hours
Now the average speed of the tuck to cover total distance:
Average speed = Total distance / Total time
Average speed = (40 + 40) / (0.5 + 1)
Average speed = 53.33 km/h
What is a short circuit?
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Answer:
A short circuit is an abnormal connection between two nodes of an electric circuit intended to be at different voltages. This results in an electric current limited only by the Thévenin equivalent resistance of the rest of the network which can cause circuit damage, overheating, fire or explosion.
hope it helps.Please give me brainliest O:-)
Answer:
A short circuit is an electrical circuit that allows a current to travel along an unintended path with no or very low electrical impedance.
Do any of y’all know the answer to this? Please help, I’ve been stuck on this question forever
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Answer:
I think it's B , maybe wrong tho....
I WILL MARK YOU THE BRAINLIEST NO LINKS
What type of friction is acting on the airplane?
sliding friction
static friction
fluid friction
rolling friction
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Answer:
I believe it's sliding friction.
Explanation:
write a short note on Andromeda galaxy.
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Answer:
[tex]\sf\pink{Andromeda \: galaxy}[/tex]
The Andromeda is a galaxy which is nearest to the milky way. It is also named as Messier 31 or M31 or NGC 224. It is a spiral galaxy located at a distance of approximately 2.5 million light years from earth.
another name Andromeda in Hindi is Vaikunth.
Explanation:
The Andromeda Galaxy (IPA: /ænˈdrɒmɪdə/), also known as Messier 31, M31, or NGC 224 and originally the Andromeda Nebula (see below), is a barred spiral galaxy approximately 2.5 million light-years (770 kiloparsecs) from Earth and the nearest major galaxy to the Milky Way.
Number of stars: ~1 trillion (1012)
Right ascension: 00h 42m 44.3s
Reason whether or not work is done in the following cases:
A. a basketball player shoots a free throw.
B. a peasant pulls a rope tied to a donkey without being able to displace it from its position.
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Answer:
A work is done because the object moved
B no work is done because the donkey didnt move
Explanation: