Answer:
D. Freezing?
Explanation:
Get water, put it in the freezer, turns into ice after a few hours.
Read each example and identify whether the data are observations or inferences from observations. The fish’s ventral fin measured 8.5 cm long.
Answer:
Observation
Inference
Inference
Observation
Inference
Explanation:
41. 2072 Set E Q.No. 11 A source of sound produces a note of
512 Hz in air at 17°C with wavelength 66.5 cm. Find the ratio
of molar heat capacities at constant pressure to constant
volume at NTP. Densities of air and mercury at NTP are
1.293 kg/m3 and 13600 kg/m3 respectively.
Ans: 1.36
You are pulling with 57 N on a heavy bookshelf, but the bookshelf doesn't move. What is the force of static friction in Newtons acting on the bookshelf?
Answer:
57N
Explanation:
Since the bookshelf isn't moving, the force you're exerting on the shelf must be equal to the force of static friction
So the force of static friction is 57N
How does Newton’s first second and third laws apply to eating your breakfast
Answer:
Newton's third law states that for every action (force) in nature there is an equal and opposite reaction. In other words, if object A exerts a force on object B, then object B also exerts an equal and opposite force on object A. Notice that the forces are exerted on different objects. However much you push your fork in the food, that much a dent it will cause.
Explanation:
Answer:
¡I hope it helps you! :) .................
An object has a mass of 50 kg on Earth. What would be the mass of that object in the Moon
It would be 50 kg.
Mass doesn't change.
Weight can.
Approximate the human form as an unclothed vertical cylinder of 0.3 m diameter and 1.75 m length with a surface temperature of 30 oC.(a)Calculate the heat loss in a 10 m/s wind at 20 oC.(b)What is the heat loss if the skin is covered with a thin layer of water (i.e., sweat) at 30 oC and the relative humidity of the air is 60 %
Answer:
[tex]q=1118.865W[/tex]
Explanation:
From the question we are told that
Diameter of the cylinder [tex]D=0.3m[/tex]
Length of the cylinder [tex]L=1.75m[/tex]
Surface temperature of cylinder [tex]T_s=30 \textdegree C=303k[/tex]
Speed of air [tex]V=10m/s[/tex]
Temperature of air [tex]T=20 \textdegree C[/tex]
Generally the equation for Reynolds number is mathematically given by
[tex]Re_D=\frac{VD}{v}[/tex]
where
[tex]v=15.27*10^-^6[/tex]
[tex]Re_D=\frac{10*0.3}{15.27*10^-^6}[/tex]
[tex]Re_D=1.96*10^5[/tex]
Generally the equation for Nusselt number is mathematically given by
[tex]N_u=0.6(Re_D)^{0.6}(Pr)^{0.37}[/tex]
where
Prandtl number
[tex]Pr=0.71[/tex]
[tex]N_u=0.6(Re_D)^{0.6}(Pr)^{0.37}[/tex]
[tex]N_u=0.6(1.96*10^5)^{0.6}(0.71)^{0.37}[/tex]
[tex]N_u=791.53[/tex]
Generally the equation for convective heat transfer is mathematically given by
[tex]h=Nu \frac{k}{D}[/tex]
where
[tex]k=25.7*10^{-3}[/tex]
[tex]h=791.53*\frac{25.7*10^{-3}}{0.3}[/tex]
[tex]h=67.81W/m^2K[/tex]
Generally the equation for surface area of a cylinder is mathematically given by
[tex]A=\pi DL[/tex]
[tex]A=\pi *0.3*1.75[/tex]
[tex]A=1.65m^2[/tex]
Generally the equation for convective heat transfer is mathematically given by
[tex]q=h4(T_s-T_{inty)}[/tex]
[tex]q=(67.81)*1.65*(30-20)\\[/tex]
[tex]q=1118.865W[/tex]
Why is this true? Why is this true? Photons of lower-frequency light don't have enough energy to eject an electron. The electric field of low-frequency light does not vibrate the electrons rapidly enough to eject them. The number of photons in low-frequency light is too small to eject electrons. Low-frequency light does not penetrate far enough into the metal to eject electrons. Request Answer
Answer:
the only correct answer is: Photons of lower-frequency light don't have enough energy to eject an electron
Explanation:
This question is in the model of the photoelectric effect, where some electrons are expelled from the metal by the action of a ray of light.
This effect was explained by Einstein supposes that the light rays are formed by photons and the energy of these photons is given by the Planco relation
K = h f - Ф
where K is the kinetic energy of the ejected electrons and Ф is the work function, it keeps the electrons inside the material.
When analyzing this expression there is a minimum frequency (threshold) for which K = 0
hf = Ф
Below this frequency the photons in the light beam do not have the energy to expel the electrons from the material.
Let's examine the answers
a) True. You agree with the above
b) False. The analysis is in terms of individual shock
c) False. The expulsion does not have to do with the number of photons but with the energy of each one
therefore the only correct answer is: Photons of lower-frequency light don't have enough energy to eject an electron
why does ice melt faster in water than in oil when both liquids are at the same temperature
Answer:
Because water has a high specific heat, each little bit of water flowing past can give lots of thermal energy to the ice cube. Oil has a smaller specific heat, and so more oil has to flow past to give the same amount of heat energy to the ice cube. ... Colder oil will melt ice less rapidly than warmer oil or water
Proton traveling across a capacitor A proton enters with a velocity v between the plates of a capacitor as shown in the figure. What is the direction of the magnetic field needed so that the proton continues its trajectory, undeflected? Explain each step of your reasoning.
Answer:
Please see the direction of force in the attachment
Explanation:
As the particle enters the capacitor, it experiences electric. In order to move in the same direction as the electron was moving before entering the capacitor, the force due to the electric field of capacitor must be balanced by the magnetic field.
The direction of particle is shown in the attachment.
As we know,
Force = q (v *B)
A 30 kg child went down a 10 m tall slide. Assuming no energy was lost as friction, what was the child's velocity when he reached the
bottom?
I
Calculate the net force for each of the following:
a.
20 N to the right and 30 N to the right:
Answer and Explanation:
A.
There would be a net force of 50 N going to the right.
Since both forces are going right, they add onto the force amount.
#teamtrees #PAW (Plant And Water)
What are the issues that hinders efforts to achieve sustainability?
Answer:
who will solve environmental problems, who is responsible for environmental problems, and who pays the cost of implementing solutions
Explanation:
A woman has one damaged fallopian tube. The damage completely blocks the opening of the tube at the ovary. How will this most likely affect her fertility?
Her likelihood of conceiving will be reduced by at least 50%.
Her eggs, if fertilized, will not implant properly.
Her eggs will not mature inside the ovary.
Her chances of conceiving twins will be doubled.
Answer:Her likelihood of conceiving will be reduced by at least 50%.
Explanation:
EDGE 2020
Answer:
Her likelihood of conceiving will be reduced by at least 50%
Explanation:
took the test on edge, got it right
Will give brainliest!!
How much KClO3 is needed to make a saturated solution in 100 mL of water at 70⁰ C?
Answer:
iam not sure but I think its NaNO3
HELP PLEASE
Two 24 ohm resistors are in parallel and placed across a 12 V battery. What is the current in each branch of the circuit?
20 A
0.0125 A
0.5 A
.
Answer:
.5 A
Explanation:
describe the human condition before Science and technology was practice.
which of the following statements about blood alcohol concentration (BAC) are true?
A. its illegal for a driver under 21 years of age of to drive with a BAC of 0.02% or above
B. it is illegal for a driver at any age to drive with a BAC of 0.08% or above
C. Both A and B are true
D. Neither A or B
A 6.25 g quarter sits 25 cm from the axis of rotation on a turntable that has a period of rotation of 1.8 seconds.
What must the coefficient of static friction be in order to keep the quarter from sliding outward when the
turntable is in motion?
The coefficient of static friction be in order to keep the quarter from sliding outward when the turntable is in motion will be 0.31.
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.
On resolving the given force and acceleration in the different components and balancing the equation gets. The friction force balances centripetal force.
The given data in the problem will be;
m is the mass =6.25 g
r is the radius =25 cm=0.25 m
t is the time = 0.18 sec
μ is the coefficient of static friction =?
[tex]\rm F_c= mw^2r \\\\ f= \mu mg \\\\ F_C=f\\\\ mw^2r= \mu mg \\\\ \rm \mu = \frac{\omega^2r}{g} \\\\ \rm \mu = (\frac{2\pi}{1.8} )^2\frac{0.25}{9.81} \\\\ \rm \mu = 0.31[/tex]
Hence the coefficient of static friction will be 0.31.
To know more about friction force refer to the link;
https://brainly.com/question/1714663
Please PLEASE HELP ASAP
A student placed four objects on a plastic tray: a rock, an eraser, a wood block, and an ice cube. The student slowly lifts the tray and measures the height at which each object begins to slide in order to compare the friction of each object. The table above shows the results. In a separate experiment the student used the same objects and tray, but glued a piece of gritty sandpaper to the tray. What results would be expected? A) The items would slide faster at the same heights. B) The items would start to slide when the tray is not lifted as high. C) The items would not slide at all, no matter how high the tray is raised. D) The tray would need to be raised higher before the items start to slide.
Answer:
D) The tray would need to be raised higher before the items start to slide.
Explanation:
The tray would need to be raised higher due to the gritty sandpaper causing it to have more grip or fraction between the two surfaces. In the first experiment it would have a smooth surface to slide across but in the second experiment it would have a rougher surface to slide across.
Example: It would be like taking two different kinds of shoes like tennis shoes and football cleets. Then seeing which one has more traction when going up a hill.
Hope this helps!!
Lithium was one of the metals studied by the American physicist Robert Millikan in his research on the photoelectric effect. When illuminated with blue light of frequency 6.64 x 10" Hz, the photoelectrons ejected from a lithium surface have a maximum kinetic energy of 0.332 eV. What is the threshold frequency for lithium? For this problem, let the value of Planck's constant, h, be 6.63 x 10J's
Answer:
f = 7.9487 10¹³ Hz
Explanation:
The photoelectric effect was correctly explained by Einstein assuming that the radiation is composed of photons, which behave like particles.
hf = K + Ф
It indicates the frequency and the kinetic energy, let's look for the work function
Ф = hf - K
let's reduce the magnitudes to the SI system
K = 0.332 eV (1.6 10⁻¹⁹ J / 1 eV) = 0.5312 10⁻⁻¹⁹ J
let's calculate
Ф = 6.63 10⁻⁻³⁴ 6.64 10¹¹ - 0.5312 10⁻¹⁹
Ф = 4.40 10⁻²² - 0.5312 10⁻¹⁹
Ф = 5.27 10⁻²⁰ J
for the minimum frequency that produces photoelectrons, the kinetic energy is zero
hf = Ф
f = Ф / h
f = 5.27 10⁻²⁰ / 6.63 10⁻³⁴
f = 7.9487 10¹³ Hz
Which direction do longitudinal waves travel?
Answer:
If the particles of the medium vibrate in a direction parallel to the direction of propagation of the wave, it is called a longitudinal wave. In longitudinal waves, the particle movement is parallel to the direction of wave propagation.
Explanation:
You and a friend are playing with a bowling ball to demonstrate some ideas of Rotational Physics. First, though, you want to calculate the Rotational Kinetic Energy of the bowling ball as it rolls down a sidewalk without slipping. This means it has both linear kinetic energy and rotational kinetic energy. A bowling ball can be modeled as a solid sphere rotating about its center. This bowling ball has a mass of 6.40 kg and a radius of 0.130 m. You'll need to look up the equation for the Moment of Inertia in your textbook. It is rotating with an angular velocity of 16.0 radians / second in the counter-clockwise (or positive) direction. You can use this to determine the linear velocity of the bowling ball (since it is rolling without slipping). What is the Total Kinetic Energy of the bowling ball
Answer:
K_{total} = 19.4 J
Explanation:
The total kinetic energy that is formed by the linear part and the rotational part is requested
[tex]K_{total} = K_{traslation} + K_{rotation}[/tex]
let's look for each energy
linear
[tex]K_{traslation}[/tex] = ½ m v²
rotation
[tex]K_{rotation}[/tex] = ½ I w²
the moment of inertia of a solid sphere is
I = 2/5 m r²
we substitute
[tex]K_{total}[/tex] = ½ mv² + ½ I w²
angular and linear velocity are related
v = w r
we substitute
K_{total} = ½ m w² r² + ½ (2/5 m r²) w²
K_{total} = m w² r² (½ + 1/5)
K_{total} = [tex]\frac{7}{10}[/tex] m w² r²
let's calculate
K_{total} = [tex]\frac{7}{10}[/tex] 6.40 16.0² 0.130²
K_{total} = 19.4 J
HELP PLZZZZZ
Vitiligo is an example of a condition that comes from
A. your habits
B. your predisposed genetics
C. your social network
D. your physical environment
Answer:
the answer is b vitiligo is a genetic skin condition
As an admirer of Thomas Young, you perform a double-slit experiment in his honor. You set your slits 1.01 mm apart and position your screen 3.09 m from the slits. Although Young had to struggle to achieve a monochromatic light beam of sufficient intensity, you simply turn on a laser with a wavelength of 639 nm . How far on the screen are the first bright fringe and the second dark fringe from the central bright fringe
Answer:
[tex]0.00195\ \text{m}[/tex]
[tex]0.00293\ \text{m}[/tex]
Explanation:
m = Order = 1
D = Distance between screen and slit = 3.09 m
d = Slit distance = 1.01 mm
[tex]\lambda[/tex] = Wavelength = 639 nm
Distance from the first bright fringe from the central bright fringe is given by
[tex]y=\dfrac{m\lambda D}{d}\\\Rightarrow y=\dfrac{1\times 639\times 10^{-9}\times 3.09}{1.01\times 10^{-3}}\\\Rightarrow y=0.00195\ \text{m}[/tex]
Distance from the first bright fringe from the central bright fringe is [tex]0.00195\ \text{m}[/tex]
Distance from the second dark fringe from the central bright fringe is given by
[tex]y=(m+\dfrac{1}{2})\dfrac{\lambda D}{d}\\\Rightarrow y=(1+\dfrac{1}{2})\dfrac{639\times 10^{-9}\times 3.09}{1.01\times 10^{-3}}\\\Rightarrow y=0.00293\ \text{m}[/tex]
Distance from the second dark fringe from the central bright fringe is [tex]0.00293\ \text{m}[/tex].
Question 9 of 10
What happens to light as it moves at an angle into a medium that has a higher index of refraction?
A. It slows down, and the angle decreases.
B. It speeds up, and the angle increases.
C. It slows down, and the angle increases.
D. It speeds up, and the angle decreases.
Answer:
v = C / n light slows entering a medium of higher index of refraction
ni sin theta i = nr sin theta r Snell's Law where i refers to incidence and r refers to refraction
sin theta r = (ni / nr) sin theta i
So if the index of refraction is greater than the angle of incidence then the light ray would be refracted towards the normal
Answer:
A. It slows down, and the angle decreases.
Explanation:
got it right, trust
An example of conservation of angular momentum is jumping on a Merry-Go-Round. Watch this video (it starts part way through but the only thing you miss is the people pushing the Merry-Go-Round) to see someone jumping on a Merry-Gr-Round in motion like this problem. You can model the Merry-Go-Round as a solid disk with a radius of 2.70 m and a mass of 77.0 kg. Initially the Merry-Go-Round has an angular velocity 7.40 radians / second. Then the person jumps on and change the Moment of Inertia of the system. The person lands on the outer edge of the Merry-Go-Round and has a mass of 58.0 kg. What is the final angular velocity of the system after the person jumps on
Answer:
ωf = 2.95 rad/sec
Explanation:
Assuming no external torques acting while the person jumps on, total angular momentum must be conserved.Angular momentum for a rotating rigid body can be expressed as follows:[tex]L = I * \omega (1)[/tex]
where I = moment of inertia regarding the rotating axis, and ω= angular velocity.Since total angular momentum must be conserved, this means that the following equality must be satisfied:[tex]L_{o} = L_{f} (2)[/tex]
The initial angular momentum, taking into account that the Merry-Go-Round can be modeled as solid disk, can be expressed as follows:[tex]L_{o} = I_{o} * \omega_{o} = \frac{1}{2}* M* R^{2}* \omega_{o} =\\ \frac{1}{2} * 77.0 kg* (2.70m)^{2}* 7.40 rad/sec = 2076.92 kg*m2*rad/sec (3)[/tex]
The final angular momentum, is just the product of the new moment of inertia times the final angular velocity.The new moment of inertia, is just the sum of the original moment of inertia I₀ and the moment of inertia due to the person that jumps on.Assuming that we can treat him as a point mass, his moment of inertia is just the product of his mass times to the distance to the axis of rotation (the radius of the Merry-Go-Round) squared.So, we can write the new moment of inertia If as follows:[tex]I_{f} = I_{o} +( m_{p} * R^{2}) = (\frac{1}{2} * M* R^{2}) + ( m_{p} * R^{2}) =\\ (\frac{1}{2} * 77.0 kg* (2.70m)^{2}) +( 58.0 kg * (2.70m)^{2}) = \\ 280.67 kg*m2 + 422.82 kg*m2 = \\ 703.49 kg*m2 (4)[/tex]
The final angular momentum can be written as follows:[tex]L_{f} = I_{f} * \omega_{f} (5)[/tex]
Since (3) and (5) must be equal each other, replacing If by its value from (4) in (5), we can solve for ωf, as follows:[tex]\omega_{f} = \frac{L_{o} }{I_{f}} = \frac{2076.92kg*m2*rad/sec}{703.49kg*m2} = 2.95 rad/sec (6)[/tex]
Why is no image formed when an object is at the focal point of a converging lens?
Answer:
the refracted rays neither converge nor diverge. After refracting, the light rays are traveling parallel to each other and cannot produce an image.
Explanation:
Consider the reaction below Na2CO3 (aq) + CaCl2 (aq) CaCO3 (s) + 2NaCl (aq) If the releases 39.4 kJ of energy, how many kilocalories does it release? (1 cal = 4.184 J) (Round off answer to 2 decimal place)
Answer: 9.42
Explanation: yes
please help asap
Ms. Brando’s students are studying forces. She has assigned a fun task: designing a balloon car. The students must design a car and see which model will travel the greatest distance. The basic design of the cars can be seen here. First the balloon is inflated and attached to the car. It is important to keep the balloon closed. Once attached to the car, the stem of the balloon is opened and air rushes out through the straw. The air goes one way; the car moves in the other direction. There are no restrictions on the design other than the students must use the materials given to them by Ms. Brando. What is the source of the force that moves the car? A) The circumference of the balloons. B) The friction between the wheels and the track surface. C) The air rushing out of the balloon through the straw. D) The mass of the car: the lighter the car the farther it moves.
Answer: a
Explanation:
when a car dives on a road it a makes friction but it need something to push it or start it which is the balloon in this example
(sorry if im wrong)
Which of these is an example of tertiary prevention?
A. Getting screened for skin cancer
B. Avoiding smoking and drinking alcohol
C. Dialysis for damaged kidneys
D. Washing hands
Explanation:
because a tertiary prevention is when the person is already infected with the disease
