Valid results are only obtained if each tube is identical because; effective comparison of the tested blood each time can only be achieved if the testing model is constant in which case each tube is identical.
Discussion:
During scientific tests such as that described in the question; it is important to keep all parameters of testing constant.
This is so because, the utmost motive of the testing model is to draw comparison. It is on this note that valid results are only obtained if each tube is identical.
Read more:
https://brainly.com/question/25786185
In what part of the electromagnetic spectrum do the biggest telescopes on earth operate?.
Explanation:
Notice it says above that the largest optical telescopes in the world are reflectors. Optical telescopes collect visible light. Even larger telescopes are built to collect light at longer wavelengths radio waves.
Can Hotspots can be found at the edges of tectonic plates?
Answer:
No.
Explanation:
Hot spots don't appear at the barriers of tectonic plates, instead, they originate at hot centres known as mantle plumes. Mantle plumes exist below the tectonic plates and may develop a string of volcanoes on the Earths surface.
The drag force on a falling coffee filter can be modeled as a linear function with respect to velocity, F⃗ D =−bv, where b is a positive constant related to the surface area and shape of the coffee filter. The teacher demonstrates how the value of constant b can be determined by releasing coffee filters from rest and having them fall toward a motion detector, as shown. The students repeat the activity and use the motion detector to measure the position, velocity, and acceleration of different coffee filters as they fall. Which of the following would provide the data needed to determine the value of b ?
Newton's second law and graphical analysis allow us to find the correct answer for the measure of the constant b is:
D) Stack several filters to change the mass measure the acceleration of the system.
Newton's second law establishes a relationship between the net force, the mass and the acceleration of the bodies.
∑ F = m a
Where the bold letters indicate vectors, F is the force, m the mass and the acceleration of the body.
They indicate that the drag force on the filters is
F = - b v
Where b is a positive constant that depends on the shape and area of the filter and v is the speed of the filter.
Let's write Newton's second law.
W - fr = ma
W -bv = ma
In the experiment the students indicate that they can measure the position, velocity and acceleration of the body.
Based on the above, if we place several filter weights and measure their speed and acceleration in each case, we can make a graph of velocity versus acceleration, we can take the value of the constant b from the slope.
Let's analyze the different answers:
A) False. The constant b depends on the shape of the filter therefore it must be kept constant.
B) False. The constant depends on the area, so it must be kept constant.
C) May be. In this case, since we have the terminal velocity, the acceleration is zero, Newton's second law remains.
B v - W = 0
b = [tex]\frac{W}{v}[/tex]
The problem with the method is the difficulty of measuring the compression terminal velocity.
D) True. According to the discussion of the velocity versus acceleration. graph, the constant b is equal to the slope of the graph.
E) May be. The problem with this method is finding a reliable value for the terminal velocity.
In conclusion, using Newton's second law and graphical analysis we can find the correct answer for the measure of the constant b is:
D) Stack several filters to change the mass measure the acceleration of the system.
Learn more here: brainly.com/question/2441565
write two example in which chemical energy is converted into heat energy
Answer:
batteries in an electric heater, a nuclear power plant
Explanation:
sorry if it wrong g
The mercury in a barometer of a cross-sectional area 1 cm² stands at 75 cm, and the space above it is 9 cm in length. What
volume of air, measured at 3. The mercury in a barometer of a cross-sectional area 1 cm² stands at 75 cm, and the space above it is 9 cm in length. What
volume of air, measured at atmospheric pressure, would have to be admitted into the space to cause the column of the mercury
to drop to 59 cm?
The ideal gas equation and the pressure in barometer allows us to find the amount of air that we must introduce into the barometer for the change in height of the mercury column is:
The variation of the volume is: ΔV = 7.67 cm³
Pressure is defined by the relationship between force and area.
P = F / A
The ideal gas equation establishes a relationship between pressure, volume, and temperature of an ideal gas.
PV = nR T
Where P is pressure, V is volume, and T is temperature.
Let's write this equation for two points assuming that the temperature has not changed.
P₀ V₀ = P₁ V₁
V₁ = [tex]\frac{P_o}{P_1} \ V_o[/tex] (1)
The subscript "o" is used for the start point and the subscript "1" for the end point.
The pressure in a barometer is:
P = ρ g y
They indicate the initial height of the barometer y₀=75 cm, the distance from empty space y'₀ = 9 cm and the final height of the barometer y₁ = 59 cm.
The volume of the cylinder is
V = π r² y
Let's calculate the initial volume.
V₀ = π 1 9
V₀ = 28.27 cm³
We substitute in equation 1.
V₁ = [tex]\frac{\rho \ g \ y_o}{\rho \ g \ y_1} \ V_o[/tex]
V₁ = [tex]\frac{y_o}{y_1} \ V_o[/tex]
Let's calculate.
V₁ = [tex]\frac{75}{59} \ 27.27[/tex]
V₁ = 35.94 cm³
The volume to be incremented is
ΔV = V₁ - V₀
ΔV = 35.94 - 28.27
ΔV = 7.67 cm³
Using the ideal gas equation and the pressure in barometer we can find the amount of air that we must introduce into the barometer for the change in height of the mercury column is:
The change of the volume is: ΔV = 7.67 cm³
Learn more here: brainly.com/question/17254541
how to find the latitude and longitude of an address
Answer:
To get the latitude of the address in cell B2, use the formula = GetLatitude (B2) To get the longitude of the address in cell B2, use the formula = GetLongitude (B2) To get both the latitude and longitude of the address in cell B2, use the formula = GetCoordinates (B2)
Explanation:
CAN I GET BRAINLIEST
PLEASE ANSWER NEED HELP!!!!!!!! PLEASE THE CORRECT ANSWER!!!!!!
Walter has a paper due on a novel that he has not read. He knows that his teacher will expect detailed references to the novel in his paper. He is thinking that he can listen to it while he is lifting weights and multi-task. What is the BEST response to Walter?
A.
He does not really need to concentrate on exercise, so it is fine.
B.
He would be better off focusing on his workout and then turning to the novel.
C.
If he is doing a type of exercise that allows him to stop and take notes, it is fine.
D.
Doing as many tasks as possible is generally a good idea and promotes efficiency.
PLEASE NO LINKS
Answer:
I'm no expert, but multitasking is a no bueno. Because multitasking reduces your efficiency and performance because your brain can only focus on one thing at a time. When you try to do two things at once, your brain lacks the capacity to perform both tasks successfully.
Therefore I would choose A, considering he could easily workout another time, whilst the test is a one time thing. He can't redo the test, but he can workout again. So my answer is A.
If he HAS to workout and study at the same time, then C would be appropriate.
I hope this helps!
in order to have beef becomes tender she will use
Answer:
you
Explanation:
you will be used is this frl?
The Kentucky Derby is one of the most exciting horse races run every year. In 1973, the horse Secretariat set a record that still stands. This 500-kg horse ran the 2000-m track in 120 s. What was Secretariat’s average kinetic energy? (1 kJ = 1000 J)
Need answers with explanaitions please
A. 4.2 kJ
B. 8.3 kJ
C. 69.0 kJ
D. 139.0 kJ
Answer:
C.69 kJ
Explanation:
kinetic energy
[tex] = 1 \div 2mv {}^{2} [/tex]
Where does the energy released in a nuclear decay reaction come from
A. Electrons
B. Chemical bonds
C. Positrons
D. The binding energy of the nucleus
What type of energy transfer causes a sunburn?
Radiation, because particles of hot air move in space
Radiation, because electromagnetic waves transfer heat
Conduction, because hot air comes in contact with the skin
Conduction, because invisible light carries heat from the sun
Pacificaly what is the right answer A? B? C? or D? which one
Answer:
radiation
Explanation:
Answer:
B is most likely forgive me if im wrong
Explanation:
A bullet of mass 6.00 gg is fired horizontally into a wooden block of mass 1.20 kgkg resting on a horizontal surface. The coefficient of kinetic friction between block and surface is 0.190. The bullet remains embedded in the block, which is observed to slide a distance 0.270 mm along the surface before stopping.
(a) What was teh initial speed of the bullet?(b) What kind of collision took place between the bullet and the block? Explain your answer comparing the values of the kinetic energy before and after the collision.(c) Calculate the impulse of the block from the moment just after the impact to his final position. Analyze the result.
Answer:
A 5.00-g bullet is fired horizontally into a 1.20-kg wooden block resting on a horizontal surface. The coefficient of kinetic friction between block and surface is 0.20. The bullet remains embedded in the block, which is observed to slide 0.230 m along the surface before stopping.
Explanation:
Which two events are part of the rock cycle?
A. Existing rock is melted aboveground and erodes.
B. Existing rock is weathered by water and erodes.
C. Solid rock is heated under high pressure and melts.
D. Solid ice is warmed by sunlight and evaporates.
Answer:
Explanation:
During a collision, a 63.9-kilogram driver of a car moving at 24 m/s is brought to rest by an inflating airbag in 1.2 seconds. What is the magnitude of the force exerted on the driver by the airbag?
Hi there!
We can use impulse for this situation:
I = Δp = mΔv
Impulse = Force × time, so:
I = 63.9(24) = 1533.6 Ns
Find force by dividing by time:
I/t = 1533.6/1.2 = 1278 N
Describe at least two similarities between untraviolet rays and microwaves
Question 1
A block with a mass of 2.5 kg slides with a velocity of 3 m/s on a frictionless surface. It hits a horizontal spring with a spring constant of 10 N/m. How much is the
spring compressed when the block stops?
Answer:
The kinetic energy of the sliding block is =1/2×m×v
2
=1/2×4×2
2
=8 J
Now since there is no friction on the surface then it is a conservative system. So all the energy of the block will be transferred to the spring and will store as a potential energy. Suppose it will compress the spring by an amount of x m. So the potential energy of the spring will be =1/2×k×x
2
Equating there two energies and solving for x, we will get, 1/2×k×x
2
=8
Or 0.5(400)x
2
=8
⟹x=0.2 m.
Explanation:
How is AU different from a solar mass?
A. An AU is the distance from the black hole at the center of the galaxy to the closest planet, and solar mass represents a measurement equal to the mass of a black hole's quasar.
B. An AU is the smallest unit of measurement in quantum mechanics, and a solar mass is the largest unit of measurement in astronomy.
C. An AU is the distance from the event horizon to the singularity of a black hole, and solar mass is the distance between the two closest black holes in a galaxy.
D. An AU is the distance from the earth to the sun, and solar mass represents a measurement equal to the mass of our sun.
AU is the distance from the earth to the sun, and solar mass represents a measurement equal to the mass of our sun.
The units applied in astronomy is quite different from the units applied in daily life. The unit called astronomical units (AU) describes the distance from the earth to the sun. The unit solar mass represents the mass of the sun and is taken to be equal to 1.989 x 10^30 kilograms.
Therefore, the difference between the AU and solar mass is that; AU is the distance from the earth to the sun, and solar mass represents a measurement equal to the mass of our sun.
Learn more: https://brainly.com/question/8646601
why do we believe 90 percent of the mass of the milky way is in the form of dark matter?
Answer:
The orbital speeds of stars far from the galactic center are surprisingly high, suggesting that these stars are feeling gravitational effects from unseen matter in the halo.
The strength of the electric field 0. 5 m from a 6 µC charge is _______ N/C. (Use k = 8. 99 × 109 N•meters squared per Coulomb squared and round answer to the nearest whole number. ) 215760 539400 697976 512356.
The strength of the electric field at a distance of 0.5 m from a 6 μC punctual charge is 143,840 N/C.
We want to calculate the strength of the electric field 0.5 m (r) from a 6 μC charge (Q).
What is the electric field?The electric field (E) is a region around a charged particle or object within which a force would be exerted on other charged particles or objects.
We can calculate the electric field at some distance from a punctual charge using the following formula.
E = (k × Q) / r²
E = [(8.99 × 10⁹ N.m².C²) × (4 × 10⁻⁶ C)] / (0.5 m)² ≈ 143,840 N/C
where,
k is the Coulomb's law constant.The strength of the electric field at a distance of 0.5 m from a 6 μC punctual charge is 143,840 N/C.
Learn more about the electric field here: https://brainly.com/question/8988726
how is pure salt obtained from the sea water ?describe in brief
Answer:
Evaporation
Explanation:
Evaporation
Answer:
Salt from sea water is obtained by the process of evaporation. ... The sea water evaporates due to the sun's heat and solid salt is left behind. The left salt is collected and refined to get purified salt. Hence, salt is obtained from sea water by evaporation.
Column A
Column B
1.
Frequency
a. Ohm
2.
Amplitude for sound
b. Decibel
3
Force
C. Joule
4
Distance
d. Newton
5.
Current
e. Amperdiet
6.
Resistance
f. Meter
7.
Voltage
g. Hertz
8.
Energy
h. Volt
Answer:its 3 and 5
Explanation:
j
HELP
How much heat energy is required to raise the temperature of 37.5g of water from 23.0°C to 55.2°C? The specific heat for water is 4.184 J/g°C. (Include your calculation to receive credit.)
Answer: 5.05 J
Explanation:
Qcalorimeter: m*c* ΔT --> (37.5g)*(4.184J/g ° C)*(55.2 °C – 23.0 °C) Qcalorimeter: 5.05 J
According to specific heat capacity, 5.052 kJ of heat energy is required to raise the temperature of 37.5 g of water from 23.0°C to 55.2°C.
What is specific heat capacity?Specific heat capacity is defined as the amount of energy required to raise the temperature of one gram of substance by one degree Celsius. It has units of calories or joules per gram per degree Celsius.
It varies with temperature and is different for each state of matter. Water in the liquid form has the highest specific heat capacity among all common substances .Specific heat capacity of a substance is infinite as it undergoes phase transition ,it is highest for gases and can rise if the gas is allowed to expand.
It is given by the formula ,
Q=mcΔT
Substitution in above formula, givesQ= 37.5×4.184×32.2=5052.18 J or 5.052 kJ.
Thus , 5.052 kJ of heat energy is required to raise the temperature of 37.5g of water from 23.0°C to 55.2°C.
Learn more about specific heat capacity,here:
https://brainly.com/question/28941910
#SPJ2
how did u figure this out
Answer:
huh? figure wht out??
Explanation:
have a great day!
Answer:
What's the meaning of the phrase 'figure it out'?
figure out 1 To discover or decide something: Let's figure out a way to help. We figured out when to hold the next meeting. 2 To solve or decipher something: Can you figure this puzzle out? Late into the night, I figured out my homework
Explanation:
what is heliocentric?
Answer:
having or representing the sun as the centre, as in the accepted astronomical model of the solar system.
Explanation:
Heliocentrism is the astronomical model in which the Earth and planets revolve around the Sun at the center of the Universe. Historically, heliocentrism was opposed to geocentrism, which placed the Earth at the center.
A boy pushes a stationary box of mass 20 kg with a force of 50 N.
Calculate the acceleration of the box. (Assume that there is no friction.)
Answer:
2.5m/s^2
Explanation:
Since there is no friction, the only force acting on the box is the applied force
We can now use the equation Fnet = ma
and we can rearrange for a
a = Fnet/m
now input the values
a = 50N/20kg
a = 2.5 m/s^2
A feather drops in a vacuum. What is the feather's final velocity if it falls for 3.48s?
A. -34.1 m/s
B. 59.3 m/s
C. -59.3 m/s
D. 34.1 m/s
Answer:
34.104
Explanation:
the time * acceleration = final velocity.
so 3.48s * 9.8m/s (gravity) = 34.1 m/s
an acorn falls from a tree. ignoring air resistance, what forces are on the acorn while it’s falling?
Answer: gravity
Explanation:
Gold density = 19.30,
Silver density = 10.49,
Lead density = 11.34.
They have the same mass but are made of different metals. Each one is lowered into a beaker of water. Use the data above to decide which one will cause the biggest rise in water level.
A) Gold
B) Silver
C) Lead
D) All will cause the same rise in water level
Density of water=1g/cm^3
Now all metals has greater mass in comparison to water.
Higher the mass higher the rise[tex]\\ \sf\longmapsto Density=\dfrac{Mass}{Volume}[/tex]
[tex]\\ \sf\longmapsto Density\propto Mass[/tex]
Higher the density higher the massGold has higher mass hence it will cause the biggest rise.
Option A
Silver will cause biggest rise in water
What is density ?Density of an object is a measure of its mass per unit volume.
density = mass / volume
since all have same mass , so metal which have higher volume will cause the biggest rise in water level .
since , density is inversely proportional to volume , hence material having low density will have higher volume
hence , silver will cause biggest rise in water
correct option B) Silver
learn more about density
https://brainly.com/question/6329108?referrer=searchResults
#SPJ2
when light enters water, it bends. what does the amount of bending depend on?
Answer:
the change of speed!
Explanation:
if light speeds up or slow down more it bend more
Which of these is a likely impact of the stronger than normal trade winds on the eastern Pacific ocean?
Warm surface water builds up, causing lower than average temperature.
Warm surface water builds up, causing higher than average temperature.
Warm surface water is reduced, causing colder conditions than normal.
Warm surface water is reduced, causing hotter conditions than normal.
Just say A B C or D which one
Answer:
b i think
Explanation:
hope this helps
Answer: A B C or D which one
Explanation: