Science questions!! Please help!!
Post Assessment on Investigating the Immune System
please help!! Please choose the right answers!! Dont guess if you dont know the answers!!
Answer: i think it is for 16, Infectious diseases commonly spread through the direct transfer of bacteria. for 17 i think In biology, immunity is the capability of multicellular organisms to resist harmful microorganisms. i dont have a clue about the others but i hope this is right or atleast helps
Explanation:
Air(ideal gas) at 292.15k is expended by a piston from 600cm^3 to 900cm^3 at a temperature of 550k at 900kpa pressure. find the pressure before expansion.
Answer:
The pressure before expansion is 717.1 kPa.
Explanation:
We need to use the Ideal Gas equation to find the initial pressure:
[tex] PV = nRT [/tex]
Where:
P: is the pressure
V: is the volume
n: is the number of moles
R: is the gas constant
T: is the temperature
Since the number of moles does not change after the expansion, we need the following number of moles:
[tex] n = \frac{P_{f}V_{f}}{RT_{f}} [/tex] (1)
Where "f" is for final
Before the expansion, the pressure is:
[tex] P_{i} = \frac{nRT_{i}}{V_{i}} [/tex] (2)
By entering equation (1) into (2) we have:
[tex] P_{i} = (\frac{P_{f}V_{f}}{RT_{f}})(\frac{RT_{i}}{V_{i}}) [/tex]
[tex]P_{i} = \frac{P_{f}V_{f}T_{i}}{T_{f}V_{i}} = \frac{900 kPa*900 cm^{3}*292.15 K}{550 K*600 cm^{3}} = 717.1 kPa[/tex]
Therefore, the pressure before expansion is 717.1 kPa.
I hope it helps you!
2. A company hires a security firm to patrol their stores and watch out for thieves. What is this an example of?
In a case whereby the company hires a security firm to patrol their stores and watch for thieves, this is an example of Inventory control.
Inventory Control: What Is It?Inventory control, also known as stock control, is the procedure used to guarantee that a business has the appropriate amount of supplies on hand. As long as internal and production controls are in place, the business can meet client demand and maintain financial flexibility.
The general definition of inventory control or stock control is "the action of verifying a shop's stock." It is the process of making sure that a business has the appropriate amount of supply on hand.
Learn more about Inventory at:
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To calculate the density of an object, its mass is ________ its volume.
A
added to
B
divided by
C
multiplied by
D
subtracted by
distance moved by the effort in lifting the 5000N load to the height of 15m
Answer:
Hello There!!
Explanation:
Work done= force × distance moved
Work done=5000N×15m
Work done=75,000J
hope this helps,have a great day!!
~Pinky~
A properly exposed photograph is taken at f/16 and 1/120s. What lens opening is required if the shutter speed is 1/60s
Answer:
f / 8
Explanation:
The f-number is the ratio of the lens's focal length to its diameter and is a measure of the intensity of the light reaching the CCD. The smaller the greater the intensity of the light
I = D / f
f-number = f / D
I = 1 / f-number
the energy deposited in the CCD is proportional to the intensity of the light and the exposure time (Δt)
E = I Δt
E = 1 /f-number Δt
in the exercise they indicate that the system is well exposed (the image is sharp and clear) for fo-number = f / 16
Δt = exposure time = 1/120 s
E = [tex]\frac{1}{120} \ \ \frac{1}{fo-number}[/tex]
indicate that the exposure time has been changed to Δt = 1/60 s, which should be the f₁-number
E = [tex]\frac{1}{60} \ \ \frac{1}{f_1-number}[/tex]
the energy deposited must be the same per location we can equal the expressions
[tex]\frac{1}{120} \ \frac{1}{f_o-number} = \frac{1}{60} \ \frac{1}{f_1-number}[/tex]
f₁-number = [tex]\frac{60}{120} \ \ \frac{1}{fo-number}[/tex]
f₁-number = ½ 16
f₁-number = 8
so the system should be set to f / 8
To understand the first law of thermodynamics and its origin. By relating heat, thermal energy, and work, the first law lays the groundwork for thermodynamics. The first law of thermodynamics generalizes the concept of energy conservation to include heat energy. You are probably already aware that loss of total mechanical energy (e.g., from nonconservative forces such as friction) does not destroy energy, but rather converts mechanical energy into thermal energy. This process, as well as the reverse process (conversion of thermal energy into mechanical energy), can be described quantitatively by the first law. Like the law of mechanical energy conservation that it generalizes, the first law relates the changes in energy that occur from the beginning to the end of some process. The first law involves the following physical quantities Using your knowledge of energy conservation, express AEth in terms of Q and W. • W: work done on the system by the outside world, Q: heat added to the system by the outside world, and AEth: thermal energy change of the system.
Answer:
okay
Explanation:
What happens during nuclear fission? A) Nucleus forms from two smaller nuclei. B) two nuclei give off positrons C) A nucleus gives off an alpha particle D) Two or more nuclei forms when a larger nucleus splits
Answer:
it is d, just did the quiz. all this came from the amazing com mentor who said a was wrong and it is d, thank you.
Explanation:
This splitting of the big atomic nucleus into smaller nuclei is known as nuclear fission, and further discussion is as follows:
Nuclear fission:The neutron collides with a uranium atom that splits during the fission of nuclear, producing a tremendous quantity of energy in the form of heat produced. If a uranium atom splits, additional neutrons are extricated.
It proceeds to smash more uranium, and the cycle continues forever.The neutrons are absorbed into a nucleus in such a nuclear reactor. It transforms into uranium-236, which is extremely unstable. Its nucleus is split into two enormous shards known as 'daughter nuclei'.Therefore, the final answer is "Option D".
Find out more about the nuclear fission here:
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Your _________ is simply your weight-to-height ratio which can be calculated using certain body measurements.
O health
O size
O weight loss
O BMI
Answer:
SiZe
Explanation:
bad bunny is the best!!!
Please help to Calculate the lower and upper bound for 3.2 + 4.6
Answer:
i think it is 7.10Explanation:
I dont have an explenation
A nylon rope that has a 0.73 cm radius and is 12 meters long is used to lift a 24 kg object straight up. If the object is lifted at constant velocity, how much is the rope stretched by? The Young's modulus of the nylon is 5.0 × 109 N/m2 and use 9.81 m/s2 for the acceleration of free fall. Express your answer in centimeters and round to the nearest hundredth.
Answer:
The rope is stretched by 0.3373 cm
Explanation:
As we know
Youngs Modulus ([tex]5.0 * 10^9[/tex] N/m2) is Stress divided by strain
Stress = force/Area = (65*9.8)/(pi * (7.3*10^-3)^2)
Starin = change in length/original length of the rope = l/12 meters
Substituting the given values we get
[tex]5.0 * 10^9[/tex] N/m2 = {([tex]\frac{\frac{24*9.8}{\pi *(7.3*10^{-3})^2} }{\frac{\delta L}{L} }[/tex])
[tex]5.0 * 10^9[/tex] N/m2 = {([tex]\frac{\frac{24*9.8}{\pi *(7.3*10^{-3})^2} }{\frac{\delta L}{12} }[/tex])
[tex]\frac{\delta L}{12} = \frac{\frac{65*9.8}{pi * (7.3*10^-3)^2} }{5.0 * 10^9}[/tex]
The rope is stretched by 0.3373 cm
What is meant by density? what are its SI unite?
please answer me..
Answer:
Density, mass of a unit volume of a material substance. ... Density offers a convenient means of obtaining the mass of a body from its volume or vice versa; the mass is equal to the volume multiplied by the density (M = Vd), while the volume is equal to the mass divided by the density (V = M/d).
Explanation:
The International System of Units is the modern form of the metric system. It is the only system of measurement with an official status in nearly every country in the world
Answer:
Density is mass per unit volume
Explanation:
SI unit is kgm3
Help pls... 100points
1 Answer:
The pitch of a sound depends on
a. frequency
b. intensity
c. amplitude
d. quality
2 Answer:
The loudness of a sound depends on
a. frequency
b. intensity
c. overtones
d. timbre
3 Answer:
The number of sound waves per unit time is called
a. amplitude
b. wavelength
c. speed
d. frequency
4 Answer:
The blending of fundamental tone and overtones produces a sound's
a. intensity
b. pitch
c. timbre
d. loudness
5 Answer:
Sonar is used
a. to locate objects in water
b. to determine underwater distances
c. for both a and b
d. for neither a nor b
6 Answer:
Sounds of frequencies below 20 Hz are called
a. fundamentals
b. overtones
c. ultrasonic sounds
d. infrasonic sounds
7 Answer:
A sound is music if it has
a. a definite pitch
b. a pleasing quality
c. rhythm
d. all of these characteristics
8 Answer:
The stirrup is a part of the
a. outer ear
b. middle ear
c. inner ear
d. cochlea
9 Answer:
An example of a percussion instrument is a (an)
a. trumpet
b. harp
c. drum
d. flute
10 Answer:
The speed of sound depends on
a. temperature
b. density
c. elasticity
d. all of these factors
11 Answer:
Sounds with frequencies above 20,000 Hz are called _____.
12 Answer:
The science of sound is called _____.
13 Answer:
High-frequency waves are used in a sound navigation and ranging
system called _____.
14 Answer:
Sounds produced when sections of a string vibrate separately are
called _____.
15 Answer:
Sound without pleasing quality, identifiable pitch, and repeating
patterns is called _____.
16 Answer:
The speed of sound decreases with increasing temperature.
a. true
b. false
17 Answer:
Sound waves are transverse.
a. true
b. false
18 Answer:
The decibel is a unit of pitch.
a. true
b. false
19 Answer:
A change in the pitch of a sound due to motion of source or
receiver (observer) is called the Doppler effect.
a. true
b. false
20 Answer:
Guitars and cellos are examples of percussion instruments.
a. true
b. false
Answer:
Explanation:
1. a as pitch depends on frequency
2. b as loudness depends on intensity
3. d as that is definition of frequency
4. c as that is definition of timbre
5. c as sonar can do both
6. d as that is definition of infrasound
7. d
8. b as that is one of three bones in the middle ear
9. c as you hit the drum to make sound
10. d
11. ultrasound
12. acoustics
13. ultrasound
14. harmonics? or resonance?
15. noise
16. b
17. b
18. b
19. a
20. b
Mom cuts the cheese by pressing the knife with a force of 50N. What is the pressure of the knife blade into the cheese if the blade is 12 cm long and 0.2 mm wide?
Answer:
Pressure=Force/Area
F=50N
A= L x W
Change the units to metres
W= 0.2x10-³m
L= 12 x 10-²m
A= 0.2x10-³ x 12 x10-²
A=2.4x10^-5m²
P= 50/2.4x10^-5
= 2.08x10^6Nm-¹ ~ 2.1x10^6Nm-¹
A plane is heading south with a velocity of 150 kilometers/hour. It experiences a tallwind with a velocity of 20 kilometers/hour. Find the resultant
velocity of the plane.
A.120 kilometers/hour to the south
B.148 kilometers/hour to the north
C.170 kilometers/hour to the south
D.130 kilometers/hour to the north
E.150 kilometers/hour to the south
Answer: 170km/hr to the South
Explanation:
The resultant velocity of the plane ilwill be gotten by adding the value of the velocities of the plane with the tallwind. It should be noted that the direction of the wind is.takwn into consideration.
Therefore, the resultant velocity of the plane will be:
= 20km/hr + 150km/hr
= 170km/hr to the South
Answer:
Resultant Velocity = 20 km/h + 150 km/h = 170 km/h
Explanation:
Which of the following is a terrestrial habitat?
A) Pond B) Garden C) Lake D) River
Answer:
garden
Explanation: All the other habitats are aquatic
A satellite of mass m is in a circular orbit of radius R2 around a spherical planet of radius R1 made of a material with density ρ. ( R2 is measured from the center of the planet, not its surface.) Use G for the universal gravitational constant.
A) Find the kinetic energy of this satellite, K
Express the satellite's kinetic energy in terms of G, m, π, R1, R2, and ρ.
B) Find U, the gravitational potential energy of the satellite. Take the gravitational potential energy to be zero for an object infinitely far away from the planet.
Express the satellite's gravitational potential energy in terms of G, m, π, R1, R2, and ρ.
C) What is the ratio of the kinetic energy of this satellite to its potential energy?
Express K/U in terms of parameters given in the introduction.
Answer:
a)
get mass of planet:
ρ = M / V
V = 4/3 * R_1^3
M = ρ * V
M = ρ * 4/3 * R_1^3
equate force equations:
F = (GMm) / r^2 // r = R_2
F = ma
a = v^2/R_2
F = m * (v^2/R_2)
m * (v^2/R_2) = (GMm) / R_2^2
plug in and solve v^2:
m * (v^2/R_2) = (G * (ρ * 4/3 * R_1^3) *m) / R_2^2
v^2 = (G * ρ * (4/3) * π * R_1^3) / R_2
put into kinetic energy equation:
K = 1/2 * m * v^2
K = 1/2 * m * (G * ρ * (4/3) * π * R_1^3) / R_2
B)
givens:
U = -(GmM) / R_2
plug in mass of planet:
U = -(G * m * ρ * 4/3 * R_1^3) / R_2
C)
use previous equations and do some algebra:
K/U = (1/2 * m * (G * ρ * (4/3) * π * R_1^3) / R_2) * -(R_2 / (G * m * ρ * 4/3 * R_1^3))
K/U = -1/2
How were the barriers to critical thinking presented?
Answer:
At a personal level, barriers to critical thinking can arise through: ... self-centred or societal/cultural-centred thinking (conformism, dogma and peer-pressure) unconscious bias, or selective perception. an inability to be receptive to an idea or point of view that differs from your own (close-mindedness)
Explanation:
Conditional waves contain a crest, trough, wavelength, and amplitude
True or False?
Answer:
True
Explanation:
A ray of light traveling in water hits a glass surface. The index of refraction of the water is 1.33, and that of the glass is 1.50. At what angle with the plane of the surface must the incident ray strike the glass in order that the polarization of the reflected ray is the greatest
Answer:
[tex]\mu=41.5\textdegree[/tex]
Explanation:
From the question we are told that:
Water index of refraction [tex]i_w=1.33[/tex]
Glass index of refraction [tex]i_g=1.50[/tex]
Generally the equation for Brewster's law is mathematically given by
[tex]\theta=tan^{-1}(\frac{i_g}{i_w})[/tex]
[tex]\theta=tan^{-1}(\frac{1.50}{1.33})[/tex]
[tex]\theta=48.44 \textdegree[/tex]
Therefore Angle of incident to plane \mu (normal at 90 degree to the surface)
[tex]\mu=90\textdegree-\theta[/tex]
[tex]\mu=90\textdegree-48.44\textdegree[/tex]
[tex]\mu=41.5\textdegree[/tex]
The disk weights 40 lb and has a radius of gyration is 0.6 ft. A 15 lb/ft moment is applied and the spring has a spring constant of 10 lb/ft. The system was initially at rest and the disk is rolling without slipping. The spring is initially unstretched. Find the angular velocity of the wheel when disk moves to the right 0.5 ft.
Answer:
angular velocity = 2.6543 rad/s
Explanation:
To find the angular velocity of the wheel when the disk moves to the right 0.5 ft, we need to be aware that the spring will stretch twice the value of gyration with any slight change in the position or movement of gyration since the top of the wheel is holding the spring.
The work done here:
= ((distance moved by the wheel) X spring constant X (Final displacement^2 - Initial displacement^2)) + Mass (q2 – q1)
Where q2 = 0.5ft
q1 = 0.8 lb
Note that linear velocity = radius X angular velocity
= -0.5(10)(1^2 – 0) + 15(0.5/0.8) = 4.375 ft·lb
Then, the kinetic energy :
Since the spring is initially unstretched, the initial tension in the spring = 0
So the final tension = ((distance moved by the wheel) X (linear velocity)^2 X (angular velocity) ^2 + (distance moved by the wheel) X (linear velocity) X ( radius of gyration) ^2 X (angular velocity) ^2
= 0.5(40/32.2)(0.8w) ^2 + 0.5(40/32.2)(0.6)^2 X w2
final tension = 0.621 w2
So the angular velocity of the wheel when disk moves to the right 0.5 ft = The Initial workdone + Initial kinetic energy will be equal to the final workdone + the final Kinetic energy
0 + 4.375 ft·lb = 0.621 w2
angular velocity = 2.6543 rad/s
a man counts 6 waves on a pond in 10 seconds. the distance between them is 40 cm. what is their speed?
Answer:
so a man counts 6 waves on a pound in 10 second
Explanation:
6×10 = 60
60/40
so the answer is3
a test tube has a diameter of 3cm . how many turns would a piece of thread of length 90.42 make round test tube
Answer:
4.8 turns would be made around the tube
Explanation:
You need the circumference of the tube since it's just a lifted circle
2×pi×3=18.85
90.42/18.85=4.79
And round that to 4.8
HELP PLZ
A baseball player hits a pop-up. The ball was hit when it was 3 feet off the ground with an initial
upward velocity of 80 ft/s. How long will it take for the ball to reach a height of 10 feet off the
ground, on the way down?
Answer:
Explanation:
Use the equation
[tex]h(t)=-16t^2+v_0t+h_0[/tex]
where h(t) is the height after a certain amount of time goes by, v0t is the initial upwards velocity, and h0 is the initial height of the projectile. For us:
h(t) = 10
v0t = 80
h0 = 3 and filling in:
[tex]10=-16t^2+80t+3[/tex] and get everything on one side to factor:
[tex]0=-16t^2+80t-7[/tex]
This factors to
t = .09 sec and 4.9 sec. Let's interpret this.
The time of .09 is when the ball reached 10 feet on the way up, and
the time of 4.9 is when the ball reached 10 feet on the way back down. That's the height we need, 4.9 seconds.
Sources A and B emit long-range radio waves of wavelength 360 m, with the phase of the emission from A ahead of that from source B by 90°. The distance rA from A to a detector is greater than the corresponding distance rB from B by 130 m. What is the magnitude of the phase difference at the detector?
Answer:
[tex]X=165 \textdegree[/tex]
Explanation:
From the question we are told that:
Wavelength [tex]\lambda =360m[/tex]
Angle [tex]\theta=90 \textdegree[/tex]
Distance variation [tex]d=130m[/tex]
Generally the equation for phase difference X is mathematically given by
[tex]X=\theta+\frac{d}{\lambda}*100[/tex]
[tex]X=90+\frac{150}{360}*100[/tex]
[tex]X=165 \textdegree[/tex]
Therefore Phase difference X is given as
[tex]X=165 \textdegree[/tex]
Ice is placed in cool water. What happens to the temperature of the ice and the water?
Answer:
Explanation:
ice absorbs heat from the water. As the water molecules lose energy, they begin to slow down, and consequently to cool. So, it's kind of the opposite of what we might think: when we put ice in water, the ice doesn't give its cold to the water, it takes heat from the water.
The velocity of a particle is given by v=25t2 -80t-200, where velocity is meter per second and time is seconds. Determine the velocity for the first six seconds when acceleration is zero.
Answer:
v = 220 m / s
Explanation:
This is a kinematics exercise, the expression for velocity is
v = 25 t² - 80 t - 200
asks the velocity for time t = 6 s.
let's calculate
v = 25 6² - 80 6 - 200
v = 220 m / s
The velocity for the first six seconds when acceleration is zero is -44 m/s.
What is velocity?
The velocity of an object is the rate of change displacement with time.
The velocity of the object for the first six seconds when the acceleration is zero is calculated as follows;
[tex]a = \frac{dv}{dt} \\\\a = 50t - 80\\\\0 = 50t - 80\\\\50t = 80\\\\t = 1.6 \ s[/tex]
Velocity when time = 1.6 s
[tex]v(1.6) = 25(1.6)^2 - 80(1.6) - 200\\\\v(1.6) = -264 \ m/s[/tex]
The velocity for the first six seconds when acceleration is zero.
[tex]v = v_{a =0} + v_6\\\\v = - 264 \ + 25(6)^2 - 80(6) - 200\\\\v = -44 \ m/s[/tex]
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sino ang legendary hacker ng pilipinas?
Answer:
Onel de guzman now he's 44,the first world's computer virus has admitted to his guilt.
(●’◡’●)ﾉ (ᗒᗣᗕ)՞ ༼ つ ◕◡◕ ༽つ
what's the point of friendship?
Answer:
Friendships can have a major impact on your health and well-being, but it's not always easy to build or maintain friendships. Understand the importance of friendships in your life and what you can do to develop and nurture friendships
7
The periodic table displays
A.
only the important compounds that exist in the world.
OB.
all of the known compounds that exist in the world today.
C.
only the important elements that exist in the world.
D.
all of the known tements that exist in the world today.