Answer:
A
Explanation:
A 40kg girl and a 50kg boy are facing each other on a friction-free rollerskates. The girl pushes the boy, who moves away at a speed of 3 m/s. What is the girl's
speed?
Your answer
Answer:
Explanation:
The Law of Momentum Conservation, just like the Law of Thermodynamics about energy, says that momentum is neither created nor destroyed but is conserved, meaning it has to go somewhere. If the girl pushes the boy and they are both on friction free skates, then the girl will also react to the push. Momentum Conservation says
[tex](m_gv_g+m_bv_b)_b=(m_gv_g+m_bv_b)_a[/tex] In words this says that the mass times the velocity of the girl plus the mass times the velocity of the boy before the push has to equal the mass times velocity of the girl plus the mass times velocity of the boy after the push. Mathematically,
[tex](40.0*0+50.0*0)_b=(40.0v+50.0*-3)_a[/tex]
The left side of this is equal to 0. On the right, I made the velocity of the boy negative. We could have made it positive and it wouldn't have mattered. The sign will only be important to the result because if the sign of the girl's velocity is the same as the boy's, she is moving in the same direction as he is; if it's different, she is moving in the opposite direction.
0 = 40.0v - 150.0 and
-40.0v = -150.0 so
v = 3.75 This means that when she pushes the boy one way, mometum is conserved and she moves in the opposite direction and at a greater velocity (because her mass is less). Physics is a wonderful thing, isn't it!?
Please help me :))
Which golf ball would hit the surface with the greatest impact: a ball that fell one meter above the surface of the Earth or a ball that fell one meter above the surface of the Moon?
Answer:
the one above the surface of earth
Explanation:
earth has gravity the ball of the moon would float away
Do only number 3 and thank
Charge = 0.2 Ah is the correct answer...
A steel railroad track has a length of 79 when the temperature is 2◦C. What is the increase in the length of the rail on a hot day when the temperature is 35◦C? The linear expansion coefficient of steel is 11 × 10−6 (◦C)−1.
Answer:
We know that the length is 79 (there are no units of length in the question, so i will leave it as it is written, without units) when the temperature is 2°C.
We want to find the increase in length when the temperature is 35°C, knowing that the linear expansion coefficient is 11*10^(-6) °C^-1
The change in length is just given by the equation:
[tex]\Delta L = \alpha*L_0* (T_1 - T_0)[/tex]
where:
α = 11*10^(-6) °C^-1
T₀ is the initial temperature, so T₀ = 2°C
T₁ is the final temperature, so T₁ = 35°C
L₀ is the initial length, so L₀ = 79
Replacing these in the equation we get:
ΔL = ( 11*10^(-6) °C^-1)*79*(35°C - 2°C)
= 0.28677
So the length of the railroad will increase by 0.28677
when two capacitors are connected in series, the effective capacitance is 2.4muF and when connected in parallel, the effective capacitance is 10muF. calculate the individual capacitances.
Answer:
let one capacitor be x and other be y
[tex]in \: parallel \: connection : \\ \frac{x + y}{xy} = 10 \times {10}^{ - 6} - - - (a) \\ in \: series \: connection : \\ x + y = 2.4 \times {10}^{ - 6} - - - (b) \\ in \: (a) : \\ \frac{2.4 \times {10}^{ - 6} }{xy} = 10 \times {10}^{ - 6} \\ xy = 0.24 - - - (c) \\ from \: (b) : \\ y = (2.4 \times {10}^{ - 6} ) - x \\ \therefore \: in \: (c) : \\ x(2.4 \times {10}^{ - 6} - x) = 0.24 \\ 2.4 \times {10}^{ - 6} x - {x}^{2} = 0.24 \\ {x}^{2} - 2.4 \times {10}^{ - 6} x - 0.24 = 0 \\ x = 0.5 \\ 0.5y = 0.24 \\ y = 0.48 \\ { \boxed{ C _{1} = 0.5 \: farads}} \\ { \boxed{C _{2} = 0.48 \: farads}}[/tex]
electromotive force in a circuit;
A) causes free electrons to flow
B) increases the circuit resistance
C) maintains circuit resistance
D) it needed to make the circuit complete
Answer:
A causes free electrons to flow
Explanation:
The amount of force that causes electrons to flow in a conductor is called electromotive force.
A first aid provider is trained to do the following except:
A) diagnose the victims condition
B) recognize, asses and prioritize the need for first aid
C) seek professional medical assistance when necessary
D) provide appropriate first aid care
Dad, if you are seeing this, then I have run away. Angie has been torturing me ever since you started dating her, and I have had enough of it. I have been trying to tell you, but you would never listen. Goodbye, and Angie, if you are seeing this, I posted this on here, so you will not be able to delete anything. Have a nice life
Answer:
hey are you ok!?!?!?!
Explanation:
Is Angie your Dad new gf or wife???
Answer:
:(
Explanation:
u ok?
running away from problems only makes things worse. Your teaching urself to run. but I dont blame u
anyway hope u find what ur looking for out there!!
Which best describes the energy of a sound wave as it travels through a medium? It increases. It decreases. It remains the same. It depends on the medium.
Answer:
It depends on the medium
Explanation:
2021 edge
The energy of a sound wave decreases as it travels through a medium to another medium. Thus, the correct option is D.
What is a Sound wave?A sound wave is the pattern of disturbance which is caused by the energy which is travelling away from the source of the sound in that medium. Sound waves are the longitudinal waves. This means that the propagation of these vibration of particles is parallel to the energy which this wave propagation direction has. When the atoms in the medium are set in vibration then they move back and forth in a direction. This continuous to occur in back and forth motion resulting in a high-pressure and a low-pressure region in the medium and thus propagating sound.
Sound wave is the physical vibration wave which travel through the air to reach the ears of organisms. Sound energy is the result when force makes an object to vibrate. A wave can lose energy as it travels through a medium because the medium can also absorb the energy from the wave. The medium changes some of the acoustic energy of the sound wave into heat energy.
Therefore, the correct option is D.
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the gravity on mars is 3.8 m/s2 and you weigh 200 N. your mass will be??
Answer:
Mass = 52.63 kilograms
Explanation:
Given the following data;
Acceleration due to gravity = 3.8 m/s²
Weight = 200 N
To find mass;
Mathematically, the weight of a physical object is given by the formula;
Weight = mass * acceleration due to gravity
Substituting into the formula, we have;
200 = mass * 3.8
Mass = 200/3.8
Mass = 52.63 kg
If you want to decrease the current created by a generator what can you do?
Answer:
To decrease the current;
1) Use fewer loops or number of turns
2) Use a lower speed of rotation of the coil in the magnetic field
3) Use a weaker magnetic
Explanation:
According to Faraday's Law of induction, which is the basis of the electromagnetism, electromagnetic induction and therefore the basis of the electric generator, can be written as follows;
[tex]\epsilon = -N \cdot \dfrac{\Delta \phi}{\Delta t}[/tex]
Where;
ε = The induced voltage
N = The number of turns (loops)
ΔФ = The change in the magnetic flux
Δt = The change in the time (the duration)
Given that voltage is directly related to the current, decreasing the voltage, decreases the current
To decrease the voltage, and therefore, the current we can;
1) Reduce the number of loops in the coil
2) Increase the time change per unit change in flux by slowing down the speed of rotation of the generator
3) Decrease the amount of change in the magnetic field per turn, by using a weaker magnetic
Explique cómo es que las estrellas emiten una radiación, específicamente qué es lo que sucede a nivel atómico
Answer:
Las estrellas se forman debido a la unión de pequeños elementos y partículas como el hidrógeno y el helio que experimentan una fusión nuclear en el núcleo debido a la intensa presión para formar un nuevo átomo (como dos hidrógeno que se combinan para formar un átomo de helio) que es un proceso. que requiere una gran cantidad de energía para comenzar, por lo que cada reacción de fusión produce una gran cantidad de energía que puede mantener la reacción y equilibra la fuerza gravitacional que atrae las masas de las partículas hacia el centro de la estrella
A medida que la energía de la estrella se irradia, la superficie de la estrella cede la energía en forma de calor y luz de manera que debido a la alta temperatura de las partículas de los átomos de los elementos se mueven muy rápida y energéticamente para emitir fotones rápidamente. (alta frecuencia) que se ve como el alto brillo de la estrella
Explanation:
CAN SOMEONE PLS HELP ME ILL GIVE YOU BRAINLIEST!!!!
A 7000 N braking force is used to slow a car down. The car was traveling at 25 m/s before the
brakes were applied and was traveling at 5 m/s after 6 seconds. What is the mass of the car? (ANS:
2100 kg)
Answer:
the answer is already there lol
Explanation:
Answer:
answer is there you can see from there lol
Explanation:
Mrs. Botts applies brakes on a car help it to decelerate at the rate of -0.80m/s2. What distance is required to stop the car when it is moving 17 m/s.
Answer:
Explanation:
vf=0
vi = 17
a = -0.8
Δx = ?
vf^2 = vi^2 + 2 a Δx
Δx = (vf^2 - vi^2) / 2a
Δx = (0-17^2) / 2 (-0.8)
Δx = 180.625 m
Which force determines if an object is going to move or stay at rest?
a. Friction Force
b. Normal Force
c. Applied Force
d. Net Force
Answer:
a
Explanation:
because it's need someone moving it so it can move somewhere else
What is a sound wave?
Courtney wants to practice doing science. Which example best illustrates her
using inquiry?
A. Courtney decides to drop several different objects off her
apartment's porch to see which falls the fastest.
B. Courtney pays close attention in her physical science class to see
if her teacher explains the speed of falling objects.
C. Courtney reads about the history of the study of gravity and learns
about why scientists first studied falling objects.
D. Courtney finds a calculation that explains the speed of falling
objects. She tries to understand the calculation by writing it down.
Answer:
A
Explanation:
because she wants to practice science and A is the practical option.
Croquet balls must have a mass of 0.50 kg. A red croquet ball is moving at 5 m/s. It strikes an at-rest green croquet ball head-on and then continues to move in the same direction, but with a speed of 2 m/s. What is the final speed of the green ball?
A.
5 m/s
B.
0.5 m/s
C.
2 m/s
D.
3 m/s
Answer:
Explanation:
The Law of Momentum Conservation for us has the equation
[tex][m_rv_r+m_gv_g]_b=[m_rv_r+m_gv_g]_a[/tex] and filling in:
[tex][(.50)(5.0)+(.50)(0)]=[(.50)(2.0)+(.50)v_g][/tex] and
2.5 = 1.0 + .50v and
1.5 = .50v so
v = 3 m/s
The final speed of the green ball is 3m/s. This can be calculated by the law of conservation of momentum. Thus, the correct option is D.
What is the law of Conservation of Momentum?
The principle of the law of conservation of momentum states that if any two objects undergo collision, then the total momentum of the objects before and after the collision will be the same if there is no external force acting on the colliding objects.
The Law of Conservation of Momentum has the equation which is:
m₁ × u₁ + m₂ × u₂ = m₁ × v₁ + m₂ × v₂
where, m₁ = mass of object 1,
u₁ = initial velocity of object 1 before collision,
m₂ = mass of object 2,
v₁ = final velocity of object 1 after collision,
v₂ = final velocity of the object 2 after collision.
0.50 × 5 + 0.50 × 0 = 0.50 × 2 + 0.50 × v₂
2.5 + 0 = 1.0 + 0.50 × v₂
2.5 - 1.0 = 0.50 × v₂
1.5 = 0.50 × v₂
1.5/ 0.5 = v₂
v₂ = 3m/s
Therefore, the correct option is D.
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Some people can roll the tongue into a tube shape, while others cannot. Practicing is not likely to help because tongue-rolling is an inherited trait. The allele for rolling the tongue (R) is dominant to the allele for not being able to roll the tongue (r). Look at the Punnett square. It shows a cross between two parents with at least one R allele. Drag each option to its spot to correctly finish the Punnett square.
Hope this helps you.
When do we say that work is done?
Answer:
Work is said to be done when a force applied to an object moves that object. We can calculate work by multiplying the force by the movement of the object.
Answer:
Work is done by a force on an object if (i) a force acts on the object and (ii) the object is displaced from its original position
The two waves shown here are the same distance from point X and are traveling toward each other.
An illustration with a crest 2.0 centimeters high traveling to the right and a second 2.0 centimeters trough traveling toward the left toward point X in the material.
What is the amplitude of the resulting wave when the two waves meet at point X?
0.0 cm
1.0 cm
2.0 cm
4.0 cm
Answer:
(C) on edge.
Explanation:
Answer:
2.0
Explanation:
trust the process.
Using a 100 year time frame,what is the CO2e of 1 tonne of CO2,2 tonne or methane,and 3 tonnes of nitrous oxide
Well, let's see what we've got here:
( 4⁻³ · 3⁴ · 4² ) / ( 3⁵ · 4⁻² ) .
The two simple rules of exponents that we're
going to use here are:
-- Two multiply two numbers with the same base,
add their exponents. Like (A³) · (A²) = A⁵ .
But the bases have to be the same.
-- A negative power just means it belongs in the
other section of a fraction.
A negative power on top means it belongs on the bottom.
A negative power on the bottom means it belongs on top.
Like A⁻² means 1/A² . And 1/B⁻³ means B³ .
That's all you need in order to clean up the big fraction
in the question. But in order to see where you can use
these rules, you need to re-arrange things first.
Original: ( 4⁻³ · 3⁴ · 4² ) / ( 3⁵ · 4⁻² )
Let's send the 4⁻³
to the bottom
where it belongs: ( -- 3⁴ · 4² ) / 4³ · ( 3⁵ · 4⁻² )
Not take that 4⁻² from
the bottom, and put it on
top, where it belongs: ( 4² · 3⁴ · 4² ) / 4³ · ( 3⁵ -- )
Multiply the 4²s on top: ( 4⁴ · 3⁴ ) / ( 4³ · 3⁵ )
Now let me break this up.
Not changing anything, just
writing it in a different way: ( 4⁴ / 4³ ) · ( 3⁴ / 3⁵ )
Look at the first fraction: 4⁴ / 4³ .
Divide top and bottom by 4³ , and it becomes just 4 .
Now look at the second fraction: 3⁴ / 3⁵ .
Divide top and bottom by 3⁴ , and it becomes just 1/3 .
So in the end, we're left with just 4 / 3 .
And THAT is exactly equal to the original big messy fraction
in the question. It has exactly the same numerical value, but
you'd never know it when you see it, because it's a lot simpler.
There are a lot of other ways we could have manipulated and
massaged the original fraction, but the steps are the same:
-- Multiply numbers with the same base, by adding the exponents.
-- Remember that a number with a negative exponent belongs
in the other section of the fraction, with a positive exponent.
as light passes from water into air it has a refracted angle of 35 degrees. calculate the incident angle of the light.
hey everyone
what is optics??
Explanation:
Optics is a branch of physics that is the study of light and vision. ... The branch of physics dealing with the nature and properties of electromagnetic energy in the light spectrum and the phenomena of vision. In the broadest sense, optics deals with infrared light, visible light, and ultraviolet light.
The diameter of a copper wire is thought to be approximately 0.3mm. Which instrument should be used to obtain a more accurate measurement of the diameter of the wire? A measuring tape B metre rule C micrometer D ruler 2
Answer:
C
Explanation:
The correct answer should be the micrometer.
The micrometer is an instrument that is capable of measuring the component of an object to very high precision. It is used to obtain accurate measurements in engineering.
In the case of the copper wire, the diameter of 0.3 mm was an approximation and a more accurate measure of the diameter would be obtained by using the micrometer.
The correct option is C.
Can someone help me :)
Answer:
undergone a chemical change
Explanation:
Answer:
undergone a chemical change
The wind blows a leaf at 37.9 m/s for 118 s left. How are does the leaf go in that period of time.
A) 3.11 m, left
B) 4470 m, left
C) 80.1 m, left
D) 0.321 m, left
Explanation:
distance = velocity * time
d = 37.9 * 118
distance = 4472.2
Describe how a wind turbine generates energy.
Cuatro contenedores idénticos tienen la misma cantidad de gas helio a la misma temperatura inicial. Los recipientes también cuentan con un émbolo móvil que no permite que el helio escape. Cada muestra de gas sigue un proceso distinto como se describe a continuación: Muestra 1: 500 J de calor salen del gas y este realiza 300 J de trabajo. Muestra 2: 500 J de calor entran al gas y este realiza 300 J de trabajo. Muestra 3: 500 J de calor salen del gas y se hace un trabajo de 300 J sobre él. Muestra 4: 500 J de calor entran al gas y se hace un trabajo de 300 J sobre él.
Answer:
1) ΔE = -800 J, 2) ΔE = 200 J, 3) ΔE = -200 J, 4) ΔE = 800 J
Explanation:
For this exercise let's use the first law of thermodynamics
ΔE = Q + W
Where we will apply this expression to several cases
1) output Q = 500 J and does work of W = 300 J.
The two processes involve an energy output
ΔE = - 500 - 300
ΔE = -800 J
Therefore, the internal energy of the gas decreases by this amount,
2) enter Q = 500J and do work of W = 300 J
Positive heat is added and does negative work
ΔE = 500 - 300
ΔE = 200 J
3) they leave Q = 500 J and do (work on the gas) W = 300J
negative heat and positive work come out
ΔE = -500 + 300
ΔE = -200 J
4) heat enters Q = 500 J, work on gas W = 300 J
both positive
ΔE = 500 + 300
ΔE = 800 J
According to Archimedes' principle, when will an object float in water?
A. When its volume is less than the volume of water it displaces
B. When its weight is equal to the buoyant force exerted by the water
C. When its density is greater than the density of water
D. When its weight is greater than the weight of water it displaces
Answer:
Its B
Explanation:
a p e x
