Answer:
57.6
Explanation:
"Significant figures" refer to figures that have an actual contribution to a number's value.
They refer to all digits except those with "leading zero," which means having a zero digit before a specific number. For example, in the number 0234, the significant figures are 234.
The rule for adding and subtracting significant figures is to round off the answer to the least number of decimal places. However, when it comes to multiplying and dividing significant figures, you have round off the answer to the least number of significant digits.
Let's solve.
21.4
+15
17.17
4.003
57.573
Let's now round off to the least number of decimal places, which is the tenths. Since 0.5 is followed by a number greater than 5, we have to round it off to 6. Therefore, the answer is: 57.6
Two equal forces act at the same time on the same motionless object, but in opposite directions. Which statement best describes the object’s resulting motion? A. The object will accelerate. B. The object will change direction. C. The object will move at a constant speed. D. The object will remain motionless.
Answer:
D
Explanation:
The object will remain motionless(i just need points)
a 12-kg block is pulled by a string at a 30 degree angle. if the string exerts a 50 n force, the block accelerates at 4.13 m/s2. what is the frictional force and normal force exerted on the block?
Let, frictional force is f and normal force is N.
Balancing horizontal forces :
[tex]50cos \ 30^o - f = 12 \times 4.13\\\\f = 50cos \ 30^o - 49.56\\\\f = -6.26\ N[/tex]
Also, balancing vertical forces, we get :
[tex]N = mg + 50sin \ 30^o\\\\N =( 12\times 9.8 ) + (50\times sin \ 30^o)\\\\N = 142.6\ N[/tex]
Therefore, the frictional force and normal force is -6.26 N and 142.6 N.
room's become bright at the day time although there is no bright sunlight in the rooms why
this is give reason
Answer:
The room become bright in the day by a process call scattering of light or Rayleigh scattering.
Explanation:
It is called Rayleigh scattering or scattering of light because Rayleigh scattering is the scattering if light or electromagnetic radiation by smaller particles which have radius of less than 110 nanometer in a medium and the wavelengths of the electromagnetic. Wave or light remain unchanged. The scattering of light occur in the day time in the room and this bring of brighten up of the room.
What is the longest wavelength that can be observed in the third order for a transmission grating having 5200 slits/cm?
Answer:
641 nm.
Explanation:
Given that,
A transmission grating has 5200 slits/cm.
We need to find the longest wavelength that can be observed in the third order. Using grating equation as follows :
[tex]d\sin\theta=m\lambda[/tex] ...(1)
d is slit spacing
No fo slit per unit length :
[tex]N={5200}\ slit/cm\\\\=520000\ slits/m[/tex]
We know that, N = 1/d
For longest wavelength, θ = 90°
From equation (1)
[tex]\dfrac{\sin\theta}{m\lambda}=\dfrac{1}{d}\\\\520000=\dfrac{\sin(90)}{3\lambda}\\\\\lambda=\dfrac{1}{520000\times 3}\\\\=6.41\times 10^{-7}\ m\\\\=641\ nm[/tex]
Hence, the longest wavelength in third order for a transmission grating is 641 nm.
a water wave has a speed of 23.0 meters/second. if the waves frequency is 0.0680 hertz, what is the wavelength
Answer:
Using the Fundamental Equation of Wave, we have:
Explanation:
2 questions! most important one is the second one so answer that. only answer if the answer to the 2 question is yes. if you cant say yes to the second question then just dont answer
Explain how would you infer through an experiment that substances generate electric current.
Answer:
How will you infer with the help of an experiment that the same current flows through every part of the circuit containing three resistors R1 ,R2 and R3 in series connected to a battery of V volt.
we can connect voltmeter across each resistor
V = V1 + V2 + V3
I1 = current across resistor R1
I1 = V1/R1
similarly
I2 = current across resistor R2
I2= V2/R2
I3 = current across resistor R3
I3 = V3/R3
we will see that
I1 = I2 = I3
also it will be equal to V/(R1 + R2+R3)
in great detail, explain why big chungus is the most powerful being of all? any counter arguments?
Answer:
well for me
Explanation:
I think
Big Chungus is the greatest game know to man currently it is only available on ps4, dispite the fact I am loyal to Xbox I couldn’t help but buy a ps4 for it I have found a review from a Redditor
And also he's presence scared everyi
Answer:
big chungus is not funny, its just a big rabbit.
Explanation:
What is the minimum force require to move a 5kg wooden crate on a wooden floor?
14.7 m/s^2
20.6N
20.6 m/s^2
14.7N
You need to know the coefficient of static friction between a wooden object and a wooden surface. I'll denote it with µ. If you're given a specific value you should obviously use that.
By Newton's second law, the horizontal and vertical net forces are
• net horizontal:
∑ F = p - f = 0
• net vertical:
∑ F = n - w = 0
where
p = magnitude of the pushing force
f = mag. of friction
n = mag. of the normal force
w = weight of the crate
The second equation gives
n = w = (5 kg) (9.8 m/s²) = 49 N
Friction is proportional to the normal force by a factor of µ, so
f = µ (49 N) = 49µ N
To overcome static friction, the push has to exceed this in magnitude, so that
p > 49µ N
For instance, if p = 0.25, then p would need to greater than 12.25 N. (This example isn't particularly helpful, though, since both possibly correct options are larger than 12.25 N...)
calculate the number of molecules of hydrogen and carbon present in 4 g of methane
Answer:
Answer = 6.022×10²³ molecules of CH4 which consists of 1 mole of C atoms and 4 moles of H atoms.
What is the answer and why
Answer:
The distance between gas species are assumed to be large.
Explanation:
Hello!
In this case, since the ideal gas condition is a hypothetical state of gases at which they are at low pressure and high temperature, because it is assumed the molecules are neither attracted nor repelled by each other, we can infer that the correct statement is "the distance between gas species are assumed to be large" because the low pressure and high temperature ensure the molecules are far away from each other and therefore allowing the ideal equation to be used to model the case, otherwise a rigorous equation of state such as Peng-Robinson, Redlich-Kwong and other should be used to model it as gases actually undergo interaction between their molecules.
Best regards!
it is difficult to walk on a smooth floor why
Answer:
because theres is not enough friction so it will be super slippery
Explanation:
Can a physical guantity have unit but is dimensionless ?
I NEED THE KNOWLEDGE OF YOU SMART GUYS OUT THERE!!!!!!
...................
if a person does not just do what you told what happens
Answer:
Of course we feel bad or angry.
Explanation:
that it what i know....
3. Now use the brown knob at the opening of the hose to adjust the angle at which water comes out. When water comes out at an angle (instead of going straight up), water does not shoot as high as before. Explain your observations qualitatively.
Answer:
Due to brown knob which controls its angle.
Explanation:
When water comes out at an angle instead of going straight up, water does not shoot as high as before because its speed is controlled by the brown knob in order to throw water in another angle. If we adjust the brown knob present at the opening of hose pipe in a straight angle the water shoot very high because water moves with high pressure and no barrier is present between its way.
Which of the following statements about elements and atoms is true?
A. Atoms are the smallest unit of an element.
B. Atoms are made of particles called elements.
C. Elements are made of more than one type of atom.
D. Elements are changed into atoms by a chemical reaction.
hmu^^^^
Answer:
A. Atoms are the smallest unit of an element.
Explanation:
The correct statement from the given choices is that atoms are the smallest unit of an element.
Atoms are the smallest particles that takes part in chemical reactions and they are made up of protons, neutrons and electrons.
Elements are distinct substances that cannot be split up into simpler substances. They are made up of only one kind of atoms. Elements are not changed into atoms by chemical reactions. In chemical reactions, atoms simply recombine.Help me please I’ll give brainliest
Answer:
zoom in
Explanation:
how much work is needed to move an object 20 meters with 40 newtons of force?
Answer: c I think is the answer
Explanation:
10 POINTS BE FAST
Which statement illustrates how progress in engineering has affected the
natural environment?(please hurry)
A. Modern mining practices provide materials that can be used for
technological advances.
B. Modern mining equipment has improved
the health and safety of
workers.
C. Extracting mineral resources
with modern mining equipment
removes fertile topsoil.
D. Mining companies use modern equipment to extract mineral
resources more efficiently.
hurry please
Answer:
I think it's c or A hopes this help
help!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 39 points and will give branlist asap!
Examine the diagram below and answer the following questions for 2 points each: Identify which graph shows an object that is not moving. Explain why. Identify which graph shows an object that is speeding up over time. Explain why. Identify which graph shows an object that is moving at a constant speed. Explain why. Question 15 options:
Answer:
Graph for object that is not moving: B
Graph for object that is speeding up: D
Explanation:
A.) In order to represent that an object is not moving, you must either show that there is no velocity (0 m/s) or show a position over time graph that is a horizontal line.
Because the position is the same as time increases, the graph shows that there the object must be at rest, as there is no change in position due to velocity. (Velocity must be 0m/s)
B.) In order to represent an object is speeding up, the position time graph must either be a positive exponential function, the velocity time graph must be a positive, linear line, or the acceleration over time graph must be a positive, horizontal line.
Why is D the correct answer? Because if an object is speeding up, you know that the value of its speed (velocity) is increasing at some rate. And since speeding up refers to positive change, the function of velocity over time graph must be a positive function.
i'd like you to explain this to me, I don't have a clue on how to do this
1. I would like you to then go into detail as to why this is an important discovery or application of this scientific principle.
2. Then I would like you to explain how this applies to what we have learned.
"discovery" - Spanish flu
scientific concept/principle - exponential growth
thank you!
Answer:
Explanation:
The Spanish flu pandemic of 1918, the deadliest in history, infected an estimated 500 million people worldwide about one-third of the planet’s population and killed an estimated 20 million to 50 million victims, including some 675,000 Americans. The 1918 flu was first observed in Europe, the United States and parts of Asia before swiftly spreading around the world. At the time, there were no effective drugs or vaccines to treat this killer flu strain. Citizens were ordered to wear masks, schools, theaters and businesses were shuttered and bodies piled up in makeshift morgues.
Does this sound familiar?
Its the same thing but with a different name called the Corona virus pandemic the same thing happened in 1918 and now it is happening again in 2020 , but in in 2020 there are far less people infected by the Corona virus as compared to the Spanish flu the numbers approximate around 70 million infected and deaths are around 2 million.
The rapid spread of Spanish flu in the fall of 1918 was at least partially to blame on public health officials unwilling to impose quarantines during wartime. The public health response to the crisis in the United States was further hampered by a severe nursing shortage as thousands of nurses had been deployed to military camps and the front lines. But one of the chief reasons that the Spanish flu claimed so many lives in 1918 was that science simply didn’t have the tools to develop a vaccine for the virus. Microscopes couldn’t even see something as incredibly small as a virus until the 1930s.
That is why the Spanish Flu claimed so many lives in 1918 and the Corona Virus didn't claim that many.
The Corona Virus patients with respect to Spanish Flu patients exponentially decreased because in 2020 we had the specific tools to fight the virus and since mankind was aware when the world engrossed into the pandemic 100 years before the new the risks that it could impose on the world , People started to Quarantine themselves, more nurses/doctors are available rather than in the era of the 19th century.
Mathematically we would say that the exponential growth would be:
[tex]y=ab^x[/tex]
This is an exponential function, which means as you increase x , y increases exponentially, and where a is the initial value and b is the growth factor.
For example:
There are 100,000 cases of Coronavirus when the virus outbroke. If the number of cases doubles every week then how many cases would be there in 10 weeks?
So the solution would be
[tex]y=ab^x\\y=100000(2)^{10}\\y=102400000[/tex]
Which means people infected with the virus would be approximate 102.5 million. But since this kind of pandemic already broke out in 1918 called the Spanish flu mankind was wise and controlled its growth factor (b) by Quarantining people , shutting down businesses, schools and implying them to work from home , closing off cafeteria's restaurants for dine in purposes and just allowing take away to reduce human contact, and since 1918 we have more doctors and nurses to treat the infected in 2020 we reduced the outbreak to 70 million in about 10 months other wise it could have been 100 million in just 2.5 months as we can see.
So guys stay indoors just go out if you REALLY need something, avoid meeting others , wear masks and gloves :)
9. What happens to the energy stored in oil when you use it to
heat your house?
a. It is used up. b. It is destroyed. c. It is converted to heat
energy. d. It stays exactly the same
Answer:
it's converted to heat energy
Answer:
C. It is converted to heat energy
Explanation:
"Energy can neither be destroyed nor created"
Question 2: Start-Up
Now you will use another Tracker experiment to examine the displacement, velocity, and acceleration of a car in the x (horizontal) direction. To
begin your investigation, open the Tracker Car Start-up experiment.
Part A
Play () the video. At the end, rewind (H) and step forward (►) one frame ata time to observe the step-by-step changes in position. Based on
your observations, describe the car's displacement (distance and direction from the starting place) over time.
Answer:
The car starts moving in the positive direction at x = 0.2 seconds. Initially it moves very little, but it covers a greater distance with each time increment.
Explanation:
Answer: The car starts moving in the positive direction at x = 0.2 seconds. Initially it moves very little, but it covers a greater distance with each time increment.
Explanation: edmentum sample answer
A 4 m^3 metal block is suspended using a cable in salt water with density 1030 kg/m^3. Tension on the cable is 42600N. What is the weight of the block. What is the density of the block?
Answer:
The density of the block is 1113.216 kilograms per cubic meter.
The weight of the block is 43669.237 newtons.
Explanation:
According to the Archimedes' Principle, the drag force experimented by the metal block is equal to the weight of the volume of water displace by the block. Besides, the block has a weight that cannot be neglected and experiments a tension from the cable. Given that the metal block is suspended, then we could consider that block is at rest.
From Newton's Laws of Motion we obtain the following equation of equilibrium:
[tex]\Sigma F = T-\rho_{m}\cdot V_{m}\cdot g + \rho_{w}\cdot V_{m}\cdot g = 0[/tex] (1)
Where:
[tex]T[/tex] - Tension on the cable, measured in newtons.
[tex]\rho_{w}[/tex], [tex]\rho_{m}[/tex] - Densities of salt water and the metal block, measured in kilograms per cubic meter.
[tex]V_{m}[/tex] - Volume of the metal block, measured in cubic meters.
[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.
If we know that [tex]T = 42600\,N[/tex], [tex]\rho_{w} = 1030\,\frac{kg}{m^{3}}[/tex], [tex]V_{m} = 4\,m^{3}[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], then the density of the block is:
[tex]T+\rho_{w}\cdot V_{m}\cdot g = \rho_{m}\cdot V_{m}\cdot g[/tex]
[tex]\rho_{m} = \frac{T+\rho_{w}\cdot V_{m}\cdot g}{V_{m}\cdot g}[/tex]
[tex]\rho_{m} = \frac{42600\,N+\left(1030\,\frac{kg}{m^{3}} \right)\cdot (4\,m^{3})\cdot \left(9.807\,\frac{m}{s^{2}} \right)}{(4\,m^{3})\cdot \left(9.807\,\frac{m}{s^{2}} \right)}[/tex]
[tex]\rho_{m} = 1113.216\,\frac{kg}{m^{3}}[/tex]
The density of the block is 1113.216 kilograms per cubic meter.
Lastly, the weight of the block ([tex]W[/tex]), measured in newtons:
[tex]W = \rho_{m}\cdot V_{m}\cdot g[/tex] (2)
[tex]W = \left(1113.216\,\frac{kg}{m^{3}}\right)\cdot (4\,m^{3}) \cdot \left(9.807\,\frac{m}{s^{2}} \right)[/tex]
[tex]W = 43669.237\,N[/tex]
The weight of the block is 43669.237 newtons.
Why do hurricanes develop over oceans?
Question 5 options:
The ocean is affected by the Coriolis effect.
The ocean winds blow from north to south.
The warmer ocean adds water vapor to the air mass.
The ocean currents cause air to move toward the land.
My guess is; The warmer ocean adds water vapor to the air mass.
I'm really sorry if I'm wrong
The warmer ocean adds water vapor to the air mads
A runaway train car that has a mass of 15,000 kg travels at a speed of 5.4 m/s down a track. Compute the time required for a force of 1500 N to bring the car to rest.
The 1500 N force would need to act in the direction opposite the train car's movement, so if we take the current direction it's moving in to be positive, we have by Newton's second law
-1500 N = (15,000 kg) a → a = -0.10 m/s²
If t is the time it takes for the train to come to rest, then
-0.10 m/s² = (0 - 5.4 m/s) / t
t = (5.4 m/s) / (0.10 m/s²) → t = 54 s
When using an open flame or hot plate,
which of the following should be used
as a safety precaution to avoid burns?
A. test tube
B. beaker
C. hot pad or mit
D. safety goggles
7. an electron with initial kinetic energy of 6.0 eV encounters a barrier with height 11.0 eV. What is the probability of tunneling if he width of he barrier is a. 0.80 nm b. 0.40 nm.
Explanation:
In quantum tunneling through a brier, the energy of the tunneled particle is same but the probability amplitude is decreased.
The expression for the probability of tunneling is expressed as follows:
[tex]T=16 \frac{E}{U_{0}}\left(1-\frac{E}{U_{0}}\right) e^{-2 \sqrt{\frac{2 m\left(U_{0}-E\right)}{h}} L}[/tex]
Here, T is the transmission probability; E is the kinetic energy, U_{0} is the barrier height, $m$ is the mass of the electron, and L is the width of the barrier.
HELP WILL GIVE BRAINLIEST OF CORRECT
Answer:
B)
Explanation:
The answer is B)- The object's speed must be changing.
So will I get the Brainliest...