Answer:
in my opinion i would say that at home cares of more effective because half of the time your child is safe and sound but in child care programs sometimes you have no idea what is going on when you are not around
Explanation:
A 12.0 V storage battery is connected to three
resistors, 4.75, 14.0 and 21.0, respectively. The resistors are joined in series.
(a)Calculate the equivalent resistance.
(b)What is the current in the circuit?
Answer in units of A.
(a). The equivalent resistance of a series circuit is the SUM of the individual resistances in the circuit.
(4.75Ω + 15Ω + 21Ω ) = 39.75Ω
(b). Current = (voltage) / (resistance)
Current = (12 v) / (39.75Ω)
Current = 0.302 Amperes (rounded to the nearest MilliAmpere))
When you are driving on the freeway and following the car in front of you, how close is too close? Let's do an estimation.
1. Pick a car model (preferably the one you drive, but can also be any car of your dream), and find its stopping distance at highway speeds (you can usually find this type of data online).
2. Assuming that the car in front of you suddenly does a hard brake. For simplicity, assume that its braking performance is about the same as yours. Then also assume a reasonable amount of reaction time on your part (the time delay between seeing the brake lights lit up and applying your own brake). In order for you not to run into the car your are following, what's the closest distance you need to keep between the two cars?
3. Redo the same calculation if the vehicle in front of you is a typical big-rig truck. Find its braking data online.
4. There is a rule of thumb which says that you must stay one car length behind the car in front of you for every 10 mi/h of driving speed. From your calculation, does this rule make sense?
Answer:
1) v= 90km/h d = 70 m, 2) x₁ = v t_r, x₁ = 6.25 m, 3) x₁=6.25 no change
4) x = 22 m
Explanation:
1) for the first part, you are asked to find the minimum safety distance with the vehicle in front
The internet is searched for the stopping distance for two typical speeds on the highway
v (km/ h) v (m/s) d (m)
90 25 70
100 27.78 84
the safe distance is this distance plus the distance traveled during the person's reaction time, which can be calculated with infirm movement
v = x / t_r
x₁ = v t_r
the average reaction time is t_r = 0.25s for a visual stimulus and t_r 0.17 for an auditory stimulus
therefore the safe distance is
x_total = x₁ + d
2) The distance is the sum of the distance traveled in the reaction
x₁ = v t_r
for v = 90 km / h
x₁ = 25 0.25
x₁ = 6.25 m
for v = 100 km / h
x₁ = 27.78 0.25
x₁ = 6.95 m
the total distance is
x_total = x₁ + d
for v = 90 km / h
x_total = 25 0.25 + 70
x_total = 76.25 m
this is the distance until the cars stop and do not collide
3) the stopping distance of a truck is
v = 90 km / h d = 100 m
in this case we see that the braking distance is much higher,
the safe distance is given by the distance traveled during the reaction, as the truck brakes slower than the car this distance does not change
4) let's analyze the empirical rule: maintain the length of a car for each increase in speed of v = 10 m / h = 4.47 m / s
for the car case at v = 90km / h = 25 m / s
according to this rule we must this to
x = 25 / 4.47 = 5.6 cars
each modern car is about 4 m long so the distance is
x = 22 m
we see that this distance is much greater than the reaction distance so it does not make much sense
3)
An eagle carries a 330g snake to a height of 250 m.
What is the potential energy of the snake after the eagle carries it away?
-)))
A)
1,050,00)
B)
10,000
©
80.850)
D)
808.5)
Answer:
b
Explanation:
Answer:
The table shows the height y (in thousands of feet) of an unmanned aerial vehicle (UAV) x minutes after it begins its descent from cruising altitude. Minutes, x Height (thousands of feet), y 0,62 5,58 10,54 15,50
Your teacher then challenges you to use the items in the envelope to create a model of a carbon-14 atom. Before you begin, you and your
group brainstorm ideas for creating your model. Your group suggests the following steps:
Step
Procedure
1
use 6 red circles for the nucleus of the atom
2
use 14 red circles for the nucleus of the atom
3
add 6 blue circles to the nucleus of the atom
4
add 8 blue circles to the nucleus of the atom
5
place 14 yellow circles around the nucleus of the atom
6
place 6 yellow circles around the nucleus of the atom
Exhibits
Which of the following steps should you follow to create a correct model of a Carbon-14 atom?
O A. steps 1,4,6
O B. steps 1, 3,5
o c. steps 2, 3, 6
O D. steps 2,4,5
O
08:11
Answer:
Look it up
Explanation:
We need to use 6 red circles as well as 8 blue circles to represent the 6 protons and 8 neutrons in the nucleus, after which we need to place 6 yellow circles around the nucleus to represent the 6 electrons in the atom. is required. Thus, the correct option is A.
How to create a Carbon-14 atom?To make an accurate model of a carbon-14 atom, we need to follow the steps that represent the correct number of protons, neutrons, and electrons in a carbon-14 atom.
Carbon-14 has 6 protons and 8 neutrons, so we will use a total of 6 red and 8 blue circles around the nucleus which also has 6 electrons, so we need to put 6 yellow circles around the nucleus.
The correct steps to follow to create a model of a Carbon-14 atom are:
Step 1: Use 6 red circles for the nucleus of the atom
Step 4: Add 8 blue circles to the nucleus of the atom
Step 6: Place 6 yellow circles around the nucleus of the atom
Thus, the correct option is A.
Learn more about Carbon-14 atom, here:
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ASAP
If a cart is released with some initial
velocity, it will slowly come to a stop.
What happens to the energy of the cart's
motion?
If the cart is pulled along at a constant velocity, no acceleration, the energy of the carts motion is constant but the force pulling it adds energy continuously. Where does the extra energy go?
Answer:
A) Energy is dissipated into heat and sound energy due to Friction
B) The energy goes into heat and sound energy due to friction again, otherwise the cart would accelerate due to an unbalanced force. Therefore, we know there's friction, and the friction causes energy loss.
A student plans to determine the resistivity of a specific type of metal. To do this, the student will use wires constructed of the metal with known dimensions that are connected to a variable power source. The potential difference across and the current through each wire are measured and the resistance of each is calculated. The resistance is used to determine the resistivity. Which of the following should be kept constant to ensure that the resistivity values are consistent, and why?
a. The potential difference across the wires, because then only the currents will be different.
b. The currents in the wires, because then only the resistances will be different.
c. The lengths of the wires, because the resistivity changes with length.
d. The temperature of the wires, because resistivity changes with temperature.
Answer:
reviewing the different answers, the correct one is d
Explanation:
In the experiment to determine the resistivity of the wires, the student should use the relationship
R = ρ L / A
ρ = R A/L
in the statement they indicate that the difference that potential and current are measured, calculating the resistances from Ohm's law
V = i R
R = V / i
As resistivity is a property of the material that depends on the temperature, great care must be taken that the resistors do not change the temperature during the experiment, as this alters the resistivity value.
When reviewing the different answers, the correct one is d
The surface of the sun has a temperature of about 5,800 Kelvin. What is the average kinetic energy of particles on the surface of the sun? Please show your work
Answer:
273.15
Explanation:
So that's three over two times 1.38 times ten to the minus twenty-three joules per Kelvin, times 5500 degrees Celsius, the surface of the sun converted into Kelvin by adding 273.15. This works out to 1.20 times ten to the minus nineteen joules. So that's the average kinetic energy of hydrogen atoms.
Compare and contrast Albert Einstein and Karl Popper regarding their views on the nature and philosophy of science. Use the key concepts of each to explain their views. Consider how they begin their accounts, the arguments they make to support their views, and their key conclusions.
Answer:
Well Albert Einstein is more smarter PERIOD
Explanation:
PLEASE CLICK ON THIS IMAGE I NEED HELP
Answer:
rocks are vertical.
Explanation:
I'm so sorry if I'm wrong this is what I think
Which of the following best describes the location of the
mantle?
A
Above the crust
B
Between the crust and the lithosphere
С
Between the crust and the core
D
Beneath the core
Answer:
The mantle exists above the crust of the earth
Why are dominant alleles always shown as capital letters?
Answer:
When writing a genotype, the dominant allele is usually represented by a capital letter, while the recessive allele has a lowercase letter.
Explanation:
Please mark me brainlest.
Answer:
Because in a punnett square, dominant alleles need to be differentiated from the recessive alleles, to do this, we write the dominant alleles as capital letters.
Explanation:
When a rocket is 4 kilometers high, it is moving vertically upward at a speed of 400 kilometers per hour. At that instant, how fast is the angle of elevation of the rocket increasing, as seen by an observer on the ground 5 kilometers from the launching pad
Answer:
The angle of elevation of the rocket is increasing at a rate of 48.780º per second.
Explanation:
Geometrically speaking, the distance between the rocket and the observer ([tex]r[/tex]), measured in kilometers, can be represented by a right triangle:
[tex]r = \sqrt{x^{2}+y^{2}}[/tex] (1)
Where:
[tex]x[/tex] - Horizontal distance between the rocket and the observer, measured in kilometers.
[tex]y[/tex] - Vertical distance between the rocket and the observer, measured in kilometers.
The angle of elevation of the rocket ([tex]\theta[/tex]), measured in sexagesimal degrees, is defined by the following trigonometric relation:
[tex]\tan \theta = \frac{y}{x}[/tex] (2)
If we know that [tex]x = 5\,km[/tex], then the expression is:
[tex]\tan \theta = \frac{y}{5}[/tex]
And the rate of change of this angle is determined by derivatives:
[tex]\sec^{2}\theta \cdot \dot \theta = \frac{1}{5}\cdot \dot y[/tex]
[tex]\frac{\dot \theta}{\cos^{2}\theta} = \frac{\dot y}{5}[/tex]
[tex]\frac{\dot \theta\cdot (25+y^{2})}{25} = \frac{\dot y}{5}[/tex]
[tex]\dot \theta = \frac{5\cdot \dot y}{25+y^{2}}[/tex]
Where:
[tex]\dot \theta[/tex] - Rate of change of the angle of elevation, measured in sexagesimal degrees.
[tex]\dot y[/tex] - Vertical speed of the rocket, measured in kilometers per hour.
If we know that [tex]y = 4\,km[/tex] and [tex]\dot y = 400\,\frac{km}{h}[/tex], then the rate of change of the angle of elevation is:
[tex]\dot \theta = 48.780\,\frac{\circ}{s}[/tex]
The angle of elevation of the rocket is increasing at a rate of 48.780º per second.
ANSWER SOON
3. Let's say we have 3 kg of iron at 100 C, and it touches a 15kg iron at 20 C. Explain what is going to happen in detail in terms of internal energy, temperature, and heat. (you can explain it with just words)
Answer:
one of the mjor effects of heat transfer is temperature change
Explanation:
simple answer
An elevator filled with passengers has a mass of 1663 kg. (a) The elevator accelerates upward from rest at a rate of 1.20 m/s2 for 3.25 s. Calculate the tension in the cable (in N) supporting the elevator. 18317 Correct: Your answer is correct. N (b) The elevator continues upward at constant velocity for 8.92 s. What is the tension in the cable (in N) during this time
Answer:
(a) T = 18309.63 N = 18.31 KN
(b) T = 16314.03 N = 16.314 KN
Explanation:
(a)
The tension in an elevator while moving upward with some acceleration is given by the following formula:
[tex]T = m(g+a)\\[/tex]
where,
T = Tension = ?
m = mass = 1663 kg
g = acceleration due to gravity = 9.81 m/s²
a = acceleration of elevator = 1.2 m/s²
Therefore,
[tex]T = (1663\ kg)(9.81\ m/s^2 + 1.2\ m/s^2)\\[/tex]
T = 18309.63 N = 18.31 KN
(b)
Constant velocity means no acceleration. So, in that case, the tension will be equal to the weight of the elevator:
[tex]T = mg\\T = (1663\ kg)(9.81\ m/s^2)\\[/tex]
T = 16314.03 N = 16.314 KN
Velocity tells us not only how fast something is going, but in what direction it is traveling.
True
False
Answer:
true
Explanation:
because I tride it
Joe has a mass of 110 kg. If Joe has to climb a 10 m ladder to get to the top of a chimney, how much work did do?
4. A train starts its journey and accelerates at 5 ms 2. How long does it take for it to reach a velocity of 100 ms??
Answer:
20 seconds
Explanation:
a system of 11 protons and 15 neutrons has a net charge of
Identify two technologies that can be used to find the locations of objects. Identify the type or types of waves each
technology uses.
How do you label a bar graph of work compared with power?
Answer:
You must label the horizontal axis with the names of the airlines and the vertical axis with the number of flights. The title must clearly state what data the bar chart is showing. With larger numbers, your scale may not go up by one.
Answer:
You must label the horizontal axis with the names of the airlines and the vertical axis with the number of flights. The title must clearly state what data the bar chart is showing. With larger numbers, your scale may not go up by one.
Explanation:
can you help me please? https://brainly.com/question/22653337
What is the hottest planet in the milky way galaxy
Answer:
Venus
Explanation:
The part of the eye that gives its shape is the:
What is The first stage in cellular respiration, what cycle?
ANSWER:
What is The first stage in cellular respiration, what cycle?- GLYCOLYSIS
In glycolysis, the beginning process of all types of cellular respiration, two molecules of ATP are used to attach 2 phosphate groups to a glucose molecule, which is broken down into 2 separate 3-carbon PGAL molecules. PGAL releases electrons and hydrogen ions to the electron carrier molecule NADP+.What are the 4 stages of cellular respiration?It has four stages known as glycolysis, Link reaction, the Krebs cycle, and the electron transport chain. This produces ATP which supplies the energy that cells need to do work.In a mass spectrometer, a specific velocity can be selected from a distribution by injecting charged particles between a set of plates with a constant electric field between them and a magnetic field across them (perpendicular to the direction of particle travel). If the fields are tuned exactly right, only particles of a specific velocity will pass through this region undeflected. Consider such a velocity selector in a mass spectrometer with a 0.105 T magnetic field.
Part (a) What electric field strength, in volts per meter, is needed to select a speed of 3.8 × 106 m/s?
Part (b) What is the voltage, in kilovolts, between the plates if they are separated by 0.75 cm?
Answer:
a).[tex]$3.99 \times 10^5 \ v/m$[/tex]
b). 2.9925 kV
Explanation:
Given :
For mass spectrometer
The magnetic field = B
B = 0.105 T
a). Given speed, v = [tex]$3.8 \times 10^6 \ m/s$[/tex]
We known
[tex]$\frac{E}{B}=v$[/tex]
∴ [tex]$E= 3.8 \times 10^6 \times 0.105$[/tex]
[tex]$=3.99 \times 10^5 \ v/m$[/tex]
b). Now spectrometer, d = 0.75 cm
[tex]$d=0.75 \times 10^{-2} \ m$[/tex]
We known
[tex]$E=\frac{V}{d}$[/tex]
[tex]$V = E\times d$[/tex]
[tex]$V = 3.99 \times 10^5 \times 0.75 \times 10^{-2}$[/tex]
[tex]$V = 2.9925 \times 10^3 \ V$[/tex]
= 2.9925 kV
How does the amplitude of the wave change as you get farther from the speaker?
Answer:
The sound is perceived as louder if the amplitude increases, and softer if the amplitude decreases. ... As the amplitude of the sound wave increases, the intensity of the sound increases. Sounds with higher intensities are perceived to be louder.
A physics student sits in a chair. The chair pushes up on the student's body. Identify the other force of the interaction force pair.
Answer:
The other force is the weight of the student.
Explanation:
With respect to Newton's third law of motion, for the student to sit and balance on the chair, there must be two equal and opposite forces involved. The student applies his/ her weight on the chair which acts downwards, while the chair applies an equal but opposite force to the weight of the student.
The force applied by the chair on the student's body is counter balanced by the student's weight. Note that, if the weight of the student is greater than the opposing force from the chair, the chair would collapse.
4 people are playing a tug of war. Two are pulling on the right side. Two are pulling on the left side. On the right side, one is pulling with a force of 60 N and the other with a force of 70 N. On the left side, one is pulling with a force of 30 N. How much force should the second person on the left apply to keep the rope in equilibrium? HINT: The rope will be in equilibrium if the net force is 0.
Answer:
100
Explanation:
since the two at the left side is pulling with a force of 70 and 60 which equals to 130 for the rope to be in equilibrium, those at the left must also pull with same force. Which makes it 130-30=100N
Help please, i am lost.
Answer:
nas wr hdrtuendnetyje because
Explanation:
He-Ne Laser device emits photons of wave length 632.8 nm by rate 4.5 x 1020 photon/s, so
the power of the laser beam =
a. 3.14 W
b. 141.3 W
c. 314.1 w
d. 431.4 W
Answer: Option b.
Explanation:
We know:
Wavelength = 632.8 nm
Fluence = 4.5*10^20 photon/s
The energy of a single photon of wavelength λ is:
E = (h*c)/λ
where:
h = 6.6*10^(-34) J*s
c = 3*10^8 m/s
And we should rewrite the wave length in meters, so:
λ = 632.8 nm = 632.8*10^(-9) m
replacing these in the energy equation, we get:
E = (6.6*10^(-34)J*s)*(3*10^8 m/s)/(632.8*10^(-9) m) = 3.13*10^(-19) J
So each one of the 4.5x10^20 photon that flow each second have this energy, then the power is:
P = (3.13*10^(-19) J)*(4.5*10^20 /s) = 140.85 J/s
and 1 W = 140.85 J/S
Then the power is:
P = 140.85 W
Then the correct answer is the option b, where the units are a little bit different than mine because I used really simplified values for c and h.
Which of the following would require the greatest number of calories?
a. heating 1 g of water from 10°C to 80°C
b. heating 10 g of water from 10°C to 40°C
c. heating 100 g of water from 10°C to 20°C
d. heating 1000 g of water from 10°C to 12°C
Answer:
D
Explanation:
You are boiling more grams for more time because the more water the longer it takes which requires more calories to burn it.