Answer:
1306.67 s
Explanation:
From the question given above, the following data were obtained:
Volume of water = 70 L
Power (W) = 18000 w
Specific heat capacity (C) = 4200 J/g℃
Initial temperature (T1) = 20 ℃
Final temperature (T2) = 100 ℃
Time (t) =?
Next, we shall determine the mass of the water. This can be obtained by converting 70 L to kg. This is illustrated below:
1 L = 1 kg
Therefore,
70 L = 70 Kg
Thus, the mass of the water is 70 kg.
Next, we shall determine the heat energy involved. This is can be obtained as follow:
Mass (M) of water = 70 Kg
Specific heat capacity (C) = 4200 J/g℃
Initial temperature (T1) = 20 ℃
Final temperature (T2) = 100 ℃
Heat Energy (Q) =?
Q = MC(T2 – T1)
Q = 70 × 4200 × (100 – 20)
Q = 294000 × 80
Q = 3520000 J
Thus, the heat energy involved is 3520000 J
Finally, we shall determine the time taken.
Power (W) = 18000 w
Heat Energy (Q) = 3520000 J
Time (t) =?
Power = energy / time
18000 = 3520000 / time
Cross multiply
18000 × time = 3520000
Divide both side by 18000
Time = 3520000 / 18000
Time = 1306.67 s
need ASAP WILL MARK BRANLIEST
Answer:
pls refer to attachments
Example of first, second and third law of motion.
Examples of Newton's three law of motion.
First law of motion: A rocket being launched up in the atmosphere.
Second law of motion:while riding a bicycle, a bicycle acts as a mass and our legs pushing on the pedals of the bicycle is the force.
Third law of motion:when we jump off from the boat,the boat moves backward.
Hope,it will helpyouu!
A 1000-kg car comes to a stop without skidding. The car's brakes do 50,000 J of work to stop the car. Which of the following was the car's velocity when the brakes were initially applied?
Answer:
10m/s
Explanation:
3 QUESTIONS (SCIENCE)
First question: What can bad space weather do to earth?
Second question: What is the purpose of the United Nations Committee, and what do they do?
Third question: What protect Earth form much of the damage from space weather?
which two solids most likelyhave the lowest melting point??
Answer:
The two solids in the right boxes
Explanation:
The two solids in the right boxes will most likely have the lowest boiling point and this can be inferred from their molecular configuration.
Boiling point as physical change is determined by the intermolecular forces within a compound. Very strong intermolecular interactions will be difficult to break. This is shown by the two models in the left boxes. For the right boxes, the connections are very weak and they will have low boiling points.400 N pushes on a 25-kg box. Starting from rest, the box achieves
a velocity of 2.0 m/s in a time of 4.0 s. Find the coefficient of kinetic friction between box and
floor.
Answer:
The kinetic coefficient of friction between box and floor is 0.443.
Explanation:
Let suppose that the box is accelerated uniformly, the acceleration ([tex]a[/tex]), measured in meters per square second, is determined by the following kinematic formula:
[tex]a = \frac{v_{f}-v_{o}}{t}[/tex] (1)
Where:
[tex]v_{o}[/tex], [tex]v_{f}[/tex] - Initial and final speeds of the box, measured in meters per second.
[tex]t[/tex] - Time, measured in seconds.
If we know that [tex]v_{o} = 0\,\frac{m}{s}[/tex], [tex]v_{f} = 2\,\frac{m}{s}[/tex] and [tex]t = 4\,s[/tex], then the acceleration experimented by the box is:
[tex]a = \frac{2\,\frac{m}{s}-0\,\frac{m}{s} }{4\,s}[/tex]
[tex]a = 0.5\,\frac{m}{s^{2}}[/tex]
Based on the body diagram, we proceed to form the equations of equilibrium:
[tex]\Sigma F_{x} = P\cdot \cos \theta -\mu_{k}\cdot N = m\cdot a[/tex] (1)
[tex]\Sigma F_{y} = N - m\cdot g - P\cdot \sin \theta = 0[/tex] (2)
Where:
[tex]P[/tex] - Magnitude of the force exerted on the box, measured in newtons.
[tex]\theta[/tex] - Direction of the force exerted on the box, measured in sexagesimal degrees.
[tex]\mu_{k}[/tex] - Kinetic coefficient of friction between box and floor, dimensionless.
[tex]N[/tex] - Normal force from the floor to the box, measured in newtons.
[tex]m[/tex] - Mass of the block, measured in kilograms.
[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.
Now we proceed to solve the system of equation for the kinetic coefficient of friction between box and floor:
By (1)
[tex]\mu_{k}\cdot N = P\cdot \cos \theta -m\cdot a[/tex]
[tex]\mu_{k} = \frac{P\cdot \cos \theta - m\cdot a}{N}[/tex]
By (2)
[tex]N = m\cdot g +P\cdot \sin \theta[/tex]
And then, we get the resulting expression:
[tex]\mu_{k} = \frac{P\cdot \cos \theta - m\cdot a}{m\cdot g + P\cdot \sin \theta}[/tex] (3)
If we know that [tex]P = 400\,N[/tex], [tex]\theta = 50^{\circ}[/tex], [tex]m = 25\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex] and [tex]a = 0.5\,\frac{m}{s^{2}}[/tex], then the kinetic coefficient of friction between box and floor is:
[tex]\mu_{k} = \frac{(400\,N)\cdot \cos 50^{\circ}-(25\,kg)\cdot \left(0.5\,\frac{m}{s^{2}} \right)}{(25\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)+(400\,N)\cdot \sin 50^{\circ}}[/tex]
[tex]\mu_{k} = 0.443[/tex]
The kinetic coefficient of friction between box and floor is 0.443.
The kinetic coefficient of friction between box and floor is 0.443.It is the ratio of friction force and the normal recation force.
What is the friction force?It is a type of opposition force acting on the surface of the body that tries to oppose the motion of the body. its unit is Newton (N).
Mathematically it is defined as the product of the coefficient of friction and normal reaction.
The given data in the problem is;
F is the force =400 N
m is the mass of box= 25-kg
u is the velocity starting from rest=0
v is the velocity achieved = 2.0 m/s
t is the time = 4.0 s.
[tex]\rm \mu[/tex] is the coefficient of kinetic friction between box and floor.
The aceleration is found as;
[tex]\rm a= \frac{v_f-v_u}{t} \\\\ \rm a= \frac{2-0}{4} \\\\ \rm a= 0.5 m/sec^2[/tex]
The normal reaction force is find as;
[tex]N= mg +P sin \theta[/tex]
The cofficient of the kinetic coefficient of friction between box and floor;
[tex]\rm \mu_k = \frac{Pcos \theta - ma }{N } \\\\ \rm \mu_k = \frac{Pcos \theta - ma }{ mg +P sin \theta } \\\\ \rm \mu_k = \frac{400 cos 50^0 - 25 \times 0.5 }{ 25 \times 9.81 +400 \times sin 50^0 } \\\\ \rm \mu_k =0.443[/tex]
Hence he kinetic coefficient of friction between box and floor is 0.443.
To learn more about the friction force refer to the link;
https://brainly.com/question/1714663
Is the gravity on the moon and earth the same and why are they the same or different
given a force of 88n and an acceleration of 4m/s2 what is the mass
Answer:
The mass is 22 kilograms
Explanation:
[tex]F=ma[/tex]
[tex]88N = m(4m/s/s)[/tex]
[tex]m=\frac{88N}{4m/s^{2} }[/tex]
[tex]m=22kg[/tex]
what is the correct answer?
Answer:
The value of k is -4. Third choice
Explanation:
The Polynomial Remainder Theorem
It states that the remainder of the division of a polynomial f(x) by (x-a) is equal to f(a).
We are given the polynomial:
[tex]p(x)= x^3+kx^2+x+6[/tex]
And we also know x+1 is a factor of p(x). If x+1 is a factor of p(x), then the remainder of the division of p(x) by x+1 is zero.
Applying the remainder theorem for a = -1:
[tex]p(-1)= (-1)^3+k(-1)^2+(-1)+6=0[/tex][tex]-1 + k - 1 + 6 = 0[/tex]
Solving for k:
[tex]k = 1 + 1 - 6[/tex]
[tex]\boxed{k = -4}[/tex]
The value of k is -4. Third choice
What is the random walk?
Answer:
In mathematics, a random walk is a mathematical object, known as a stochastic or random process, that describes a path that consists of a succession of random steps on some mathematical space such as the integers.
Explanation:
What is the displacement of the particle in the time interval 7 seconds to 8 seconds? A. 0 meters B. 1.5 meters C. 3 meters D. 7 meters
Answer:
It's 1.5 meters
Explanation:
plato
An icicle falls off of a skyscraper from rest and falls for 34 seconds. How far did the icicle fall? Show all work and units. (a = g = 9.81 m/s^2) *
Explanation:
u = 0.0m/s
t = 34s
a = 9.81m/s²
Using Kinematics,
s = ut + 0.5at²
= 0 + 0.5(9.81)(34)²
= 5,670.18m.
The variables for Part I of this experiment include whether or not the car hits the barrier and the distance that the washers travel. Use the drop-down menus to identify the independent and dependent variables.
The independent variable, the one that is intentionally manipulated, is
____.
The dependent variable, the one that you measure the response in, is
___.
Answer:
1. An encounter with the barrier
2. The distance traveled by the washer.
Explanation:
Answer:
Peep above me is correct
1.An encounter with the barrier
2.The distance traveled by the washer
Explanation:
got it right on edge2020 have a nice day peeps ^w^
Please help I will send pics in return or I will mark brainliest (depending on what u want) for a good attempt and explanation.
The answer would have to be 8.47 m/s/s because the backwards pull + the rate of speed it is going would have to be added to get the answer to compensate for the backwards pull
Two balls, ball A and ball B, are dropped from the same height onto the same surface. If ball A rebounds to a higher height than ball B then:(3) A. ball A is more elastic than ball B. B. ball B is more elastic than ball A. C. not enough information is given to determine which ball is more elastic.
Answer:
its b
Explanation:
In Space, an astronaut releases a wrench from his hand. The wrench has a mass of 4 grams and is traveling with a velocity of -15m/s. The Astronaut’s mass is 70kg. What is his Velocity?
Answer:
The velocity of the astronaut is approximately 0.0008571 m/s
Explanation:
The mass of the the wrench, m₁ = 4 grams = 0.004 kg
The velocity of the wrench, v₁ = -15 m/s
The mass of the astronaut, m₂ = 70 kg
The velocity of the astronaut = v₂
Whereby the astronaut and the wrench were initially at rest, we have;
The total initial momentum = 0 kg·m/s
The total final momentum = m₁ × v₁ + m₂ × v₂ = 0.004 kg × (-15 m/s) + 70 kg × v₂
By the conservation of momentum principle, we have;
The total initial momentum = The total final momentum
Therefore, we have;
0 kg·m/s = 0.004 kg × (-15 m/s) + 70 kg × v₂
Which gives;
0.004 kg × (-15 m/s) = 70 kg × v₂
70 kg × -v₂ = 0.004 kg × (-15 m/s)
-v₂ = 0.004 kg × (-15 m/s)/(70 kg) ≈ -0.0008571 m/s
-v₂ ≈ -0.0008571 m/s
v₂ ≈ 0.0008571 m/s
The velocity of the astronaut = v₂ ≈ 0.0008571 m/s
You have a cup full of water and a bathtub full of water. Both samples of water have a temperature of 30°C. Which sample has greater amount of heat?
Answer:
temperature is -10
Explanation:
Hey, can you help me?
Answer:
The unit rate is $0.22 lb
Explanation:
The given parameters are;
The price for 18 lb = $3.99
We have;
The unit rate is the price for one unit. Whereby the unit of measurement is the lb, we have that one unit = 1 lb.
Therefore, given that 1 lb = 18 lb/18, the price of 1 lb which is the unit rate is given as follows;
18 lb price = $3.99
Divide both sides by 18 to get;
18 lb/18 = $3.99/18 = $0.221[tex]\bar 6[/tex]
Therefore, we have;
1 lb = 18 lb/18 = $0.221[tex]\bar 6[/tex]
The unit rate, which is the cost for 1 lb to the nearest hundredth = $0.22/lb.
A bicyclist initially at rest, begins pedaling and gained speed steadily for 4.80s during which she covers 37.0m What was her final speed?
Answer:
The final speed of the bicyclist is 15.44 m/s.
Explanation:
Given;
initial velocity, u = 0
time of motion, t = 4.8 s
distance covered, d = 37.0 m
The acceleration of the bicyclist is calculated as;
d = ut + ¹/₂at²
37 = 0 + ¹/₂(4.8)²a
37 = 11.52a
a = 37 / 11.5
a = 3.22 m/s²
The final speed of the bicyclist is given as;
v² = u² + 2ad
v² = 0 + 2(3.22)(37)
v² = 238.28
v = √238.28
v = 15.44 m/s
Therefore, the final speed of the bicyclist is 15.44 m/s.
All models have a limitations True or false
Answer:
The answer is True.
Explain how the shape of a river's stream bed can affect the river's speed and its power to cause erosion.
Answer:
Possiable answer by edge:
The shape of a river’s stream bed affects the speed and eroding power of a river by influencing the amount of friction between the water flowing through the river and the stream bed below. Friction is the force that opposes the motion of one surface as it moves across another surface. In a river, there is friction between the flowing water and the stream bed beneath it. Where a river is deep, less water comes into contact with the stream bed, so there is less friction. The reduced friction means there is less opposition to the water’s motion, so the river flows at a greater speed and has more kinetic energy for erosion. On the other hand, where a river is shallow, more water comes into contact with the stream bed, so there is more friction. The increased friction means there is more opposition to the water’s motion, so the river flows at a lesser speed and has less kinetic energy for erosion. Also, the roughness of a stream bed covered with boulders and other obstacles causes the water to flow through the river in a turbulent fashion. This could cause the river to move slower in some cases or erode more in other cases.
Explanation:
summary of answer:
influencing the amount of friction between the water flowing through the river and the stream bed below.
Which diagram best illustrates what happens when electromagnetic waves strike a reflective material?
Answer:
The second diagram does that
The last diagram below represents what happenes when electromagnetic waves strike a reflective material. The last diagram is showed in the image below.
Anyone.... help with this two questions...
Who was Alfred Wegener and what did he theorize?
Answer:
Who was Alfred Wegener: He was a German meteorologist and geophysicist
What did he theorize: he theorized continental drift and he also explained how all 7 continents were once together( aka Pangaea) on earth over millions of years ago.
Hope this helped a little!
Which of the following exhibit parabolic motion?
a flat rock skipping across the surface of a lake
a three-point shot in basketball
an airplane in flight at a steady cruising altitude
a ball bouncing across the room
a life preserver dropped from a stationary helicopter
Answer:
A
Explanation:
Hopefully this helps
Suggest a form of renewable energy that could be used to power an electric ticket machine that only needs to work during daylight hours.
Answer:
solar panel or wind turbine
Explanation:
Because solar panel gives energy to electricity by sun and wind turbine gives energy through wind and both are renewable
Renewable energy that could be used to power an electric ticket machine that only needs to work during daylight hours is solar energy.
What is solar energy?Solar energy is the term for solar radiation that can create heat, trigger chemical reactions, or create electricity. The total solar energy incident on Earth is far greater than the global energy needs at the moment and in the future. This highly distributed source has the ability to meet all future energy demands if properly exploited.
Due to its limitless supply and lack of pollution, solar energy is predicted to become a more appealing renewable energy source in the twenty-first century than the finite fossil fuels coal, petroleum, and natural gas.
Although sunlight is by far the most potent energy source that Earth receives from the Sun, its intensity at the surface of the planet is actually rather modest.
This is primarily due to the massive radial radiation propagating from the far-off Sun. Earth's atmosphere and clouds, which absorb or scatter as much as 54% of the incoming sunlight, cause a comparatively small additional loss.
Learn more about solar energy here:
https://brainly.com/question/9704099
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PLEASE ANSWER - WILL MARK BRAINLIEST - THANKS
List three scientific ideas, discoveries, concepts, or issues that interest you.
Answer:
Evolution, Big Bang Theory and Cell theory.
Explanation:
These theories interest me because they talk about life and how life started.
why is the horizontal component of a velocity remains constant in horizontal and inclined projection
Answer:
This is because there is no acceleration in the horizontal direction
Explanation:
This is because, the only acceleration affecting the object in horizontal and inclined projection is the acceleration due to gravity, which is directed the vertical downward direction. There is a velocity change only in the vertical direction and none in the horizontal direction because, there is no acceleration in the horizontal direction. So, its velocity remains constant.
Give an example of the Law of Conservation of Energy. Explain your example
Answer: The law of conservation of energy can be seen in these everyday examples of energy transference: Water can produce electricity. Water falls from the sky, converting potential energy to kinetic energy. This energy is then used to rotate the turbine of a generator to produce electricity.
Explanation: Thats what we learned
define relative velocity
