Answer:
Because white color reflects back the heat coming from the sun while dull colors absorb the heat.
A train 90m long stops in a train station with its front buffers in line with a lamp post on the platform. Later it starts off with an average acceleration of 0.45m/s. What will be its speed in kilometers per hour when the tail buffers pass the lamp post P?
Answer:
The speed of the train when the tail buffers pass the lamp post is 9 m/s
Explanation:
The given parameters are;
The length of the train = 90 m
The initial velocity of the train, u = 0
The average acceleration of the train, a = 0.45 m/s²
When the tail buffer pass the lamp post, P, we have;
The distance travelled, s = The length of the train = 90 m
The kinematic equation of motion is given as follows;
v² = u² + 2·a·s
Where;
v = The speed of the train when the tail buffers pass the lamp post
∴ v² = 0² + 2 × 0.45 m/s² × 90 m = 81 m²/s²
Therefore;
v = √(81 m²/s²) = 9 m/s
The speed of the train when the tail buffers pass the lamp post, v = 9 m/s.
During which step of the scientific method does a scientist determine
whether the hypothesis was supported?
A. Perform the experiment
B. Collect data
C. Draw conclusions
D. Design an experiment
SUBMN
PREVIOUS
Answer:
A
in performing the experiment the hypothesis is proved wrong or correct prediction , meaning of prediction is guessing,
hypothesis the second stage of scientific method , scientist predict or guess the answer to the problem ,
Experiment the third stage of scientific method
scientist examine the ways
"Perform the experiment" is the step of the scientific method where a scientist determines whether the hypothesis was supported.
What step of the scientific method is used to prove if the hypothesis is accepted or rejected?In the scientific method, experiments (often with controls and variables) are devised to test hypotheses. In the scientific method, analysis of the results of an experiment will lead to the hypothesis being accepted or rejected.
How do scientists determine whether a hypothesis is correct?The basic idea of a hypothesis is that there is no predetermined outcome. For a solution to be termed a scientific hypothesis, it has to be an idea that can be supported or refuted through carefully crafted experimentation or observation.
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In a Rutherford scattering experiment, alpha parti- cles having kinetic energy of 7.70 MeV are fired toward a gold nucleus that remains at rest during the collision. The alpha particles come as close as 29.5 fm to the gold nucleus before turning around. (a) Calculate the de Broglie wave- length for the 7.70-MeV alpha particle and compare it with the distance of closest approach, 29.5 fm. (b) Based on this comparison, why is it proper to treat the alpha particle as a particle and not as a wave in the Rutherford scattering experiment
(a) The de Broglie wavelength is approximately 5.175 × 10⁻¹⁵ meters. The wavelength is lesser than the distance of closest approach
(b) It is proper to treat the alpha particle as a particle and not as wave because the distance of closest approach is much larger than and not comparable to its wavelength for the alpha particle for the alpha particle to be treated as a wave
The given parameters are;
The kinetic energy of the alpha particles = 7.70 MeV = 1.23368 × 10⁻¹² J
The distance from the gold nucleus the alpha particles reach = 29.5 fm
(a) The de Broglie wavelength of a particle is given as follows;
[tex]\mathbf{\lambda = \dfrac{h}{p}}[/tex]
Where;
λ = The wavelength
h = Planck's constant = 6.62607004 × 10⁻³⁴ m²·kg/s
p = The momentum of the particle = Mass of an electron, m × Velocity, v
The mass of an alpha particle, m ≈ 6.645 × 10⁻²⁷ kg
Therefore;
[tex]\lambda = \dfrac{h}{m \times v}[/tex]
The kinetic energy of the alpha particle, K.E. = (1/2)·m·v²
∴ v = √(2 × K.E./m)
Therefore;
[tex]\lambda = \dfrac{h}{m \times \sqrt{2 \times \dfrac{K.E.}{m} } } = \dfrac{h}{ \sqrt{2 \times m \times K.E.} }[/tex]
Plugging in the values of the variables gives;
[tex]\lambda = \dfrac{6.62607004 \times 10 ^{-34} }{ \sqrt{2 \times 6.645 \times 10 ^{-27} \times 1.23368 \times 10^{-12} } } \approx 5.175 \times 10^{-15}[/tex]
The de Broglie wavelength of the alpha particle, λ ≈ 5.175 × 10⁻¹⁵ m
The distance of closest approach = 29.5 fm = 29.5 × 10⁻¹⁵ m
Compared to the distance of closest approach, the wavelength of the alpha particle is lesser than the distance of closest approach
(b) Given that the distance of closest approach is six times larger than the wavelength of the alpha particle, and alpha particle behaving as waves are expected to approach closer to the gold nucleus in the region of their wavelength before deflection, therefore, the larger distance of closest approach is indicative of a charged particle to charged particle interaction, and therefore, particle behavior of alpha particles.
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How do you format short quotations in an MLA-style document?
Answer:
To indicate short quotations (four typed lines or fewer of prose or three lines of verse) in your text, enclose the quotation within double quotation marks.
define mass defect and binding energy
Answer:
About Transcript. Nuclear binding energy is the energy required to split an atom's nucleus into protons and neutrons. Mass defect is the difference between the predicted mass and the actual mass of an atom's nucleus. The binding energy of a system can appear as extra mass, which accounts for this difference.
Explanation:
PLZ MARK AS THE BRAINLIEST
I NEED IT URGENTLY
HAVE A GOOD DAY
MAY GOD BLESS U
: )
please ans both urgent
Answer:
d I guess not sure
b if down I guess
Explanation:
if worng then plz dont say anything as I am not sure about the ans
Describe the responses of the human ear to sound waves coming from the
right side, left side, or in phase.
If the sound comes from the right side, the waves reach the right ear before the left ear. if the sound comes from the left side, the waves reach the left ear before the right ear. The difference between the phases of waves reaching both ears is detected by the ears and then interpreted by the brain
if you add km/ hr with another km/ hr what will you get
Answer:
km/hr
Explanation:
Addition and subtraction are commutative
Meaning you can add or subtract in any order because it doesn't change the sum or the difference. So it doesn't change the units.
Answer:
km/ hr + km/ hr =(km+ km)/hr=2km/hr
Explanation:
A uniform bridge span of weight 1200 kN and of
length 17.0 m rests on a support of width 1.0 m at
either end. A stationary lorry of weight 60 kN is the
only object on the bridge. Its centre of mass is 3.0m
from the centre of the bridge.
15.0 m
(a) What kind of energy is possessed by an aeroplane flying at a height of 10000 m?
Answer:
When the plane is rest position it possess potential energy. But when a aeroplane is flying at the height it possess kinetic energy. No matter what height is given.
Q- Wheel of a running vehicle has which energy?
(a) Vibrational Kinetic energy
(b) Translational Kinetic energy
(c) Rotational Kinetic energy
(d) All of the above
Answer:
Rotational kinetic energy
Explanation:
It is caused by circular motion.
Two charges 3*10^-5 C and 5*10^4 C are placed at a distance 10 cm form each other. Find the value of electrostatic force acting between them. a) 13.5 x 10^11N b) 40 x 10^11N c)180 x 10^9N d)13.5 x 10^10 N
Answer:
13.5 x 10^(11) N
Explanation:
Given :
The magnitude of charge 1 = q1 = 3 × 10^(-5) C
The magnitude of charge 2 = q2 = 5 × 10^(4) C
The distance between charges = d = 10 cm = 0.1 m
To Find :
The magnitude of electrostatic force acting between charges
Solution :
∵ Electrostatic force = F = (k × (q1) x (q2)) / r^(2)
where k = 9 × 10^(9)
i.e F = 9 × 10^(9) × (3 × 10^(-5) × 5 × 10^(4)) / (0.1)^(2)
Or, F = 9 × 10^(9) × (1.5/0.01)
∴ F = 9 × 10^(9) × 150
i.e F = 1350 × 10^(9)
or, Force = F = 1.35 × 10^(12) N
Hence, The magnitude of electrostatic force acting between charges is 1.35 × 10^(12) N => 13.5 x 10^(11)
2. ¿Puede haber trabajo en un sistema si no hay movimiento
a. Sí, si hay una fuerza siempre.
b. Sí, ya que el movimiento es sólo relativo.
c. No, ya que un sistema que no se mueve no tiene energía.
d. No, porque la ecuación de trabajo lo define.
Answer:
d. No, porque la ecuación de trabajo lo define.
Explanation:
En Física, el trabajo realizado se puede definir como la cantidad de energía transferida cuando un objeto o cuerpo se mueve a lo largo de una distancia debido a la acción de una fuerza externa.
Matemáticamente, el trabajo realizado viene dado por la fórmula;
[tex] W = F * d [/tex]
Dónde;
W es el trabajo realizado.F representa la fuerza que actúa sobre un cuerpo. d representa la distancia recorrida por el cuerpo.Por lo tanto, podemos deducir de la definición de trabajo y su fórmula que el trabajo se realiza cuando un objeto (cuerpo) se mueve una distancia o experimenta cualquier forma de desplazamiento mientras transfiere energía.
8. What type(s) of motion do the particles in a solid undergo? A. vibrational, rotational, and translational B. vibrational and rotational C. vibrational only D. rotational only
Explanation:
Particles in solids are always vibrating (moving back and forth) in place.
If we aim a radio telescope at a distant spiral arm of the Milky Way Galaxy, we will probably observe a 21-cm line. If we point a large optical telescope at this same region, we will probably not be able to detect the neutral hydrogen that gives rise to the 21-cm radio signal. Why not
Answer:
Because of the interstellar dust and interior location of the solar system.
Explanation:
We will probably not be able to detect the neutral hydrogen that gives rise to the 21-cm radio signal if we point a large optical telescope to the region because, the interstellar dust obscures the location of the spiral arm of the Milky way galaxy and this makes neutral hydrogen that gives rise to the 21-cm radio signal difficult to detect.
Also, the interior location of the solar system also makes the neutral hydrogen that gives rise to the 21-cm radio signal difficult to detect.
So, the interstellar dust and the interior location of the solar system makes it difficult to detect the neutral hydrogen that gives rise to the 21-cm radio signal with a large optical telescope.
Một dây nhôm dài 10 m khi ở 25 độ C. Biết khi nhiệt độ tăng thêm 1 độ C thì chiều dài 1m dây nhôm sẽ tăng thêm 0,024mm.
a) Tính ăng chiều dài của 1m dây nhom khi nhiệt độ tăn thêm 75 độ C
b) Tính chiều dài dây nhôm ở 75 độ C
Answer:
??????? what language is this. um A then
Use the equation d=st where d= distance, s= speed, and t= time. If you ride a skateboard at a speed of 8m/s for 12 seconds, how far do you travel
Answer:
96 meters
Explanation:
d = st
d = (8 m/s)(12 s)
d = 96 m
6x+8=32 kết quả x là bao nhiêu
Answer:
6x+8=32
6x=32-8
6x=24
x=24:6
x= 4
vậy, x =4
An open winding in an electric motor means that ____. A. a wire in a winding is broken B. the centrifugal switch to the start winding is open C. the winding is making contact with the motor frame D. one winding is making contact with another winding
Answer:
A. a wire in a winding is broken.
Explanation:
An electric circuit can be defined as an interconnection of electrical components which creates a path for the flow of electric charge (electrons) due to a driving voltage.
Generally, an electric circuit consists of electrical components such as resistors, capacitors, battery, transistors, switches, inductors, etc.
Basically, an electric circuit is considered to be open when there's a broken continuity (broken path), which causes no current to flow through the circuit.
On the other hand, a closed circuit is one in which there's a flow of current due to a complete electrical path.
On a related note, an open winding in an electric motor means that a wire in a winding is broken.
Straight wire of indefinite length (transient) passed by an electric current of 5.0 A. The magnetic field generated around this conductor at point M is 50 μT. Thus the distance from the conductor to point M is:
A. 2π cm
B. 0.2π cm
C. 2.0 cm
D. 0.20 cm
Answer:
C. 2.0 cm
Explanation:
The magnetic field around the wire at point M is given by Biot-Savart Law:
[tex]B = \frac{\mu_o I}{2\pi R}[/tex]
where,
B = Magnetic field = 50 μT = 5 x 10⁻⁵ T
I = current = 5 A
μ₀ = permeability of free space = 4π x 10⁻⁷ N/A²
R = distance of point M from wire = ?
Therefore,
[tex]5\ x\ 10^{-5}\ T = \frac{(4\pi\ x\ 10^{-7}\ N/A^2)(5\ A)}{2\pi R}\\\\R = \frac{(2\ x\ 10^{-7}\ N/A^2)(5\ A)}{5\ x\ 10^{-5}\ T}\\[/tex]
R = 0.02 m = 2 cm
Hence, the correct option is:
C. 2.0 cm
Which of the following is a contact force?
A. applied
B. electromagnetic
C. nuclear
D. gravity
applied force is a contact force
The gravitational force of the two objects is 6.67x10-11N. Explain this statement.
Answer:
it means that the force of attraction between two object in gravitation is 6.67×10-11N
It means that the force of attraction between two object in gravitation is 6.67×10-11N.
What is the formula of mass in gravitational force?The formula is g = GM/r2, Where M is the mass of the Earth, r is the radius of the Earth (or distance between the center of the Earth and you, standing on its surface), and G is the gravitational constant. G (without the subscripts) is the gravitational constant, and c is the speed of light.
What is the gravitational force between two objects?The gravitational force between two objects is proportional to their masses and inversely proportional to the square of the distance between their centers. joining the two centers of masses.
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A bullet with a mass mb=13.5 g is fired into a block of wood at velocity vb=245 m/s. The block is attached to a spring that has a spring constant k of 205 N/m. The block and bullet continue to move, compressing the spring by 35.0 cm before the whole system momentarily comes to a stop. Assuming that the surface on which the block is resting is frictionless, determine the mass mw of the wooden block.
Momentum is conserved, so the sum of the momenta of the bullet and block before collision is equal to the momentum of the combined bullet-block system,
[tex]m_bv_b+m_wv_w = (m_b+m_w)v[/tex]
where v is the speed of the bullet-block system. The block starts at rest so it has no initial momentum, and solving for v gives
[tex]v = \dfrac{m_b}{m_b+m_w} v_b[/tex]
The total work W performed by the spring on the bullet-block system as it is compressed a distance x is
[tex]W = -\dfrac12kx^2[/tex]
where k is the spring constant, and the work done is negative because the restoring force of the spring opposes the bullet-block as it compresses the spring.
By the work-energy theorem, the total work done is equal to the change in the bullet-block's kinetic energy ∆K, so we have
[tex]W_{\rm total} = W = \Delta K[/tex]
The bullet-block starts moving with velocity v found earlier and comes to a stop as the spring slows it down, so we have
[tex]-\dfrac12kx^2 = -\dfrac12(m_b+m_w)v^2 \implies kx^2 = \dfrac{{m_b}^2}{m_b+m_w}{v_b}^2[/tex]
Solve for [tex]m_w[/tex]:
[tex]m_w=\dfrac1k\left(\dfrac{m_bv_b}x\right)^2-m_b[/tex]
[tex]m_w=\dfrac1{205\frac{\rm N}{\rm m}}\left(\dfrac{(0.0135\,\mathrm{kg})\left(245\frac{\rm m}{\rm s}\right)}{0.350\,\rm m}\right)^2-0.0135\,\mathrm{kg}\approx \boxed{0.422\,\mathrm{kg}}[/tex]
Un muelle se alarga 20 cm cuando ejercemos sobre él una fuerza de 24 N. Calcula:El valor de la constante elástica del muelle
Answer:
120 Nm-1
Explanation:
Según la ley de Hooke;
F = Ke
F = fuerza sobre el resorte
K = constante de fuerza
e = extensión
Por eso;
K = F / e
K = 24N / 20 × 10 ^ -2m
K = 120 Nm-1
Provide two positives and two negatives the Sarah‘s family would face if they switched to organic farming
Answer:
Organic farming would have higher costs, and would be more complex than conventional farming. However, the Suarez family could charge a higher price for organic produce. This type of farming also would be better for the land.
Explanation:
Answer expert verified for the same question. (question/4178423)
We use __force to do different force. 1) pulling 2)pushing 3)gravity 4)muscular
Answer:
gravity
Explanation:
We use gravity to do different force.
express in standard form
(I)0.000038
Answer:
3.8 x 10^-5
Explanation:
all you doing is putting it in the standard form I hope this help
help with this physics question please :)
Answer:
is that rm in you profile pic
help me with this one
Answer:
Explanation:
2. a
3. c
Luis rushes 40m toward his truck. He notices he forgot his shoes and returns back to his house. His total travel time is 60s.
What is Luis’s average speed over the 60s?
What is Luis average velocity over the 60s?
1. The average speed of Luis over the 60 s is 1.33 m/s
2. The average velocity of Luis over the 60 s is zero.
1. The average speed can be calculated with the following equation:
[tex] S = \frac{d}{t} [/tex]
Where:
d: is the total distance traveled
t: is the total time = 60 s
The total distance can be calculated by the sum of the distance traveled to the truck (40 m) and the distance traveled to his home (the same 40 m), as follows:
[tex] d = 40 m + 40 m = 80 m [/tex]
So, the average speed is:
[tex] S = \frac{d}{t} = \frac{80 m}{60 s} = 1.33 m/s [/tex]
Hence, Luis's average speed over the 60 s is 1.33 m/s.
2. Now, the average velocity is a vector given by:
[tex]v = \frac{\Delta x}{\Delta t} = \frac{x_{f} - x_{i}}{t}[/tex]
Where:
[tex]x_{f}[/tex]: is the final distance traveled (the way to his home) = 40 m
[tex]x_{i}[/tex]: is the initial distance traveled (the way to his truck) = 40 m
Δt: is the total time = t = 60 s
Given that Luis in his journey, returns to the same starting point (his house), the total displacement is zero, and so the average velocity is also zero:
[tex]v = \frac{x_{f} - x_{i}}{t} = \frac{40 m - 40 m}{60 s} = 0[/tex]
Therefore, Luis's average velocity over the 60 s is zero.
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As shown in the figure below, Luis rushes 40 m toward his truck. He notices he forgot his shoes and returns back to his house. His total travel time is 60 s.
Answer:
What is Luis’s average velocity over the 60 s period?
Answer: 0 m/s
What is Luis’s average speed over the 60 s period?
Answer: 1.33 m/s
