Answer:
okay
Explanation:
please I don't know
an arrow is shot horizontally from the top of a tower at a speed of 15m/s and hits the ground with a speed of 25m/s. calculate the height of the tower
The height of the tower is 20.41 m.
To determine the height of the tower, we need to understand the concept of the energy conservation principle since the speed and acceleration due to gravity are involved in the system.
What is the energy conservation principle?The principle of energy conservation lets us know that in an isolated system, energy can neither be created nor destroyed.
It can be expressed using the formula:[tex]\mathbf{mgh = \dfrac{1}{2}mv_1^2 = \dfrac{1}{2}mv_2^2}[/tex]
From the parameters given:The initial speed [tex]v_1[/tex] = 15 m/sThe final speed [tex]v_2[/tex] = 25 m/sBy applying the energy conservation principle, we have:
[tex]\mathbf{gh +\dfrac{1}{2}v_1^2 = \dfrac{1}{2}v_2^2}[/tex]
[tex]\mathbf{h = \dfrac{v_2^2- v_1^2 }{2 \times g}}[/tex]
[tex]\mathbf{h = \dfrac{25^2-15^2 }{2 \times 9.8}}[/tex]
h = 20.41 m
Learn more about the energy conservation principle here:
https://brainly.com/question/22236101
PLEASE HELP! I'LL GIVE BRAINLEST
Answer:
1.62 m/s²
Explanation:
The force of Earths gravity keeps earth in orbit true or false
Answer:
True
Explanation:
The force of gravity keeps all of the planets in orbit around the sun
True. The force of gravity keeps all of the planets in orbit around the sun.
What is Gravity?
The force that pulls items toward the center of a planet or other entity is called gravity. All of the planets are kept in orbit around the sun by gravity.
Gravity applies to everything that has mass. Gravity is stronger for objects with higher mass. Along with distance, gravity weakens as well. Therefore, the gravitational pull of two things becomes stronger the closer they are to one another.
The mass of the Earth is what creates gravity. The combined gravitational force of all of its mass acts on the mass in your body.
Therefore, True. The force of gravity keeps all of the planets in orbit around the sun.
To learn more about gravity, refer to the link:
https://brainly.com/question/4014727
#SPJ2
Please help due today
Answer:
8
Explanation:
(8√2)² = x² + x²
8² × √2² = 2x²
64 × 2 = 2x²
128 = 2x²
64 = x²
x = 8
give me brainliest please
Which cloud types would most likely indicate that a thunderstorm is on the way?
cirrus clouds
dull, gray, stratus clouds
cumulus clouds that are small and round
cumulus clouds that are tall with a flat top
Answer:
The aswer is D
Explanation:
Answer:
d
Explanation:
cumulus clouds that are tall with a flat top
A 0.545-kg ball is hung vertically from a spring. The spring stretches by 3.56 cm from its natural length when the ball is hanging at equilibrium. A child comes along and pulls the ball down an additional 5cm, then lets go. How long (in seconds) will it take the ball to swing up and down exactly 4 times, making 4 complete oscillations before again hitting its lowest position
Answer:
t = 9.52 s
Explanation:
This is an oscillatory motion exercise, in which the angular velocity is
w = [tex]\sqrt{ \frac{k}{m} }[/tex]
Let's use hooke's law to find the spring constant, let's write the equilibrium equation
F_e - W = 0
F_e = W
k x = m g
k = [tex]\frac{m g}{x}[/tex]
k = 0.545 9.8 /0.0356
k = 150 N / m
now the angular velocity is related to the period
W = 2π / T
we substitute
4π² T² = k /m
T = 4pi² [tex]\sqrt{ \frac{m}{k} }[/tex]
we substitute
T = 4 pi² [tex]\sqrt{ \frac{0.545}{150} }[/tex]
T = 2.38 s
therefore for the spring to oscillate 4 complete periods the time is
t = 4 T
t = 4 2.38
t = 9.52 s
Which statement is true about how early humans met their needs?
Answer:
they were hunter gatherers
Explanation:
what do solar winds and the earths magnetic field create
Answer:
bc earth rotates
3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P3==D---------- :P
Explanation:
Answer:
The interaction between the solar wind and Earth's magnetic field, and the influence of the underlying atmosphere and ionosphere, creates various regions of fields, plasmas, and currents inside the magnetosphere such as the plasmasphere, the ring current, and radiation belts.
Explanation:
At the end of the passage, Sarah says to Emma, “You’re not the only one with tricks up your sleeves.” Explain what Sarah means by this. Use information from the passage to support your answer.
Answer:
Sarah plans to use trickery and cunning to get back at Emma. Sarah thinks she is smarter than Emma.
Explanation:
i think this is right i dont know tho
Plz help
What factors determine
how the speed of the marbles changes in a
collision?
Answer:
Force,friction,inertia and momentum
Explanation:
The speed that the marble is moving at can be determined by the amount of force used when pushed or pulled and what kind of surface it's on.Momentum is also a factor because of the mass of the marbles.
A textbook of mass 2.10 kg rests on a frictionless, horizontal surface. A cord attached to the book passes over a pulley whose diameter is 0.100 m , to a hanging book with mass 3.10 kg . The system is released from rest, and the books are observed to move a distance 1.29 m over a time interval of 0.850 s . Part A What is the tension in the part of the cord attached to the textbook
Answer:
the tension in the part of the cord attached to the textbook is 7.4989 N
Explanation:
Given the data in the question;
As illustrated in the image below;
first we determine the value of the acceleration,
along vertical direction; we use the second equation of motion;
y = ut + [tex]\frac{1}{2}[/tex]a[tex]_y[/tex]t²
we substitute;
0 m/s for u, 1.29 m for y, 0.850 s for t,
1.29 = 0×0.850 + [tex]\frac{1}{2}[/tex]×a[tex]_y[/tex]×(0.850)²
1.29 = 0.36125a[tex]_y[/tex]
a[tex]_y[/tex] = 1.29 / 0.36125
a[tex]_y[/tex] = 3.5709 m/s²
Now when the text book is moving with acceleration , the dynamic equation will be;
T₁ = m₁a[tex]_y[/tex]
where m₁ is the mass of the text book ( 2.10 kg )
a[tex]_y[/tex] is the vertical acceleration ( 3.5709 m/s² )
so we substitute
T₁ = 2.10 × 3.5709
T₁ = 7.4989 N
Therefore, the tension in the part of the cord attached to the textbook is 7.4989 N
A dump truck contains a load of soil. Which action will leave the dump truck's
inertia unchanged?
A. Dump out some of the soil.
B. Add gas to its fuel tank.
C. Add more soil.
D. Increase the force applied by the engine.
Answer:
D
Explanation:
This will not change the weight and therefore not change the inertia
A dump truck contains a load of soil. The action that will leave the dump truck's inertia unchanged is that increase the force applied by the engine. Hence, option D is correct.
What is inertia?A body's ability to resist being propelled into motion or, if already moving, to modify the direction or magnitude of its velocity is known as inertia.
An object's lethargy is a passive quality that prevents it from doing anything other than obstructing active forces and torques. The only reason a moving body continues to move is the lack of a force that might slow it down, alter its trajectory, or accelerate it. This is not due to inertia.
A body's inertia moment about a certain axis and its mass, which determine how resistant it is to the application of forces to that axis, respectively, are two statistical measures of inertia.
To know more about Inertia:
https://brainly.com/question/3268780
#SPJ2
True or false? Pls help
False.
Tripling the height will triple the potential energy.
Speed has nothing to do with potential energy.
using the human species as an example, explain what is meant by variation of traits
If a virtual image is formed 10.0 cm along the principle axis from a convex mirror of focal length-15.0 cm, how far is the object from the mirror
Answer:
U=30cm
Explanation:
All you have to do is to put
Mirror formula , 1/f=1/u + 1/v
You should be careful in sign convention .
Virtual image is negative
we take focal length of convex lens negative even if its not given and so on...
What is Force ?.............
Answer:
Push or pull of an object is considered a force. Push and pull come from the objects interacting with one another. Terms like stretch and squeeze can also be used to denote force.
In Physics, force is defined as:
The push or pull on an object with mass that causes it to change its velocity.
Force is an external agent capable of changing the state of rest or motion of a particular body. It has a magnitude and a direction. The direction towards which the force is applied is known as the direction of the force and the application of force is the point where force is applied.
A certain type of laser emits light that has a frequency of 4.9 x 1014 Hz. The light, however, occurs as a series of short pulses, each lasting for a time of 2.9 x 10-11 s. The light enters a pool of water. The frequency of the light remains the same, but the speed of light slows down to 2.3 x 108 m/s. In the water, how many wavelengths are in one pulse
Answer:
N = 1.42 × 10⁴ cycles
Explanation:
Given that:
frequency f = 4.9 × 10¹⁴ Hz
Time = 2.9 × 10⁻¹¹ s
Speed = 2.3 × 10⁸ m/s
Recall that:
wavelength [tex]\lambda = \dfrac{c}{f} \\ \\[/tex]
Horizontal distance [tex]\Delta x = ct[/tex]
Number of wavelengths [tex](N) = \dfrac{\Delta x}{\lambda}[/tex]
[tex]N = \dfrac{ct}{c/f} \\ \\ N= ft[/tex]
N = (4.9 × 10¹⁴ cycles/s) (2.9 × 10⁻¹¹ s)
N = 14210
N = 1.42 × 10⁴ cycles
Medical devices implanted inside the body are often powered using transcutaneous energy transfer (TET), a type of wireless charging using a pair of closely spaced coils. And emf is generated around a coil inside the body by varying the current through a nearby coil outside the body, producing a changing magnetic flux. Calculate the average induced emf, of each 10-turn coil has a radius of 1.50 cm and the current in the external coil varies from its maximum value of 10.0 A to zero in 6.25 x10-6s.
Answer:
[tex]0.475\ \text{V}[/tex]
Explanation:
n = Number of turns = 10
r = Radius = 1.5 cm
I = Current = 10 A
t = Time = [tex]6.25\times 10^{-6}\ \text{s}[/tex]
[tex]\mu_0[/tex] = Vacuum permeability = [tex]4\pi\times 10^{-7}\ \text{H/m}[/tex]
Magnetic field is given by
[tex]B=\dfrac{\mu_0I}{2r}\\\Rightarrow B=\dfrac{4\pi 10^{-7}\times 10}{2\times 1.5\times 10^{-2}}\\\Rightarrow B=0.00042\ \text{T}[/tex]
EMF is given by
[tex]\varepsilon=\dfrac{nBA}{t}\\\Rightarrow \varepsilon=\dfrac{10\times 0.00042\times \pi (1.5\times 10^{-2})^2}{6.25\times 10^{-6}}\\\Rightarrow \varepsilon=0.475\ \text{V}[/tex]
The average induced emf is [tex]0.475\ \text{V}[/tex].
PLEASE HELP! I'LL GIVE BRAINLEST
Answer:
In this conversation the Neil astronaut is right
The indices of refraction for her contact lens, cornea, and the fluid behind her cornea are 1.6, 1.4, and 1.3, respectively. Light is incident from air onto her contact lens at an angle of 30 ∘∘ from the normal of the surface. At what angle is the light traveling in the fluid behind her cornea?
Answer:
[tex]23^{\circ}[/tex]
Explanation:
n = Refractive index of air = 1
[tex]n_1[/tex] = Refractive index of contact lens = 1.6
[tex]n_2[/tex] = Refractive index of cornea = 1.4
[tex]n_3[/tex] = Refractive index of fluid = 1.3
From Snell's law
[tex]n\sin30^{\circ}=n_1\sin\theta\\\Rightarrow \theta=\sin^{-1}\dfrac{1\sin30^{\circ}}{1.6}\\\Rightarrow \theta=18.21^{\circ}[/tex]
[tex]n_1\sin\theta=n_2\sin\theta_1\\\Rightarrow \theta_{1}=\sin^{-1}\dfrac{1.6\times \sin18.21^{\circ}}{1.4}\\\Rightarrow \theta_1=20.92^{\circ}[/tex]
[tex]n_2\sin\theta_1=n_3\sin\theta_3\\\Rightarrow \theta_3=\sin^{-1}\dfrac{1.4\sin20.92^{\circ}}{1.3}\\\Rightarrow \theta_3=22.62^{\circ}\approx 23^{\circ}[/tex]
The angle is the light traveling in the fluid behind her cornea is [tex]23^{\circ}[/tex].
The angle is the light traveling in the fluid will be 23⁰. Light is traveling in a particular direction with an angle.
What is snell law?"The ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant, for the light of a given color and for a given set of media,
The given data in the problem is;
n is the refractive index of air = 1
n₁ is the refractive index of contact lens = 1.6
n₂ is the refractive index of cornea = 1.4
n₃ is the refractive index of fluid = 1.3
According to Snell's law. The formula for Snell's law is
[tex]\rm n sin30^0 = n_1 sin\theta \\\\ \theta = sin^{- 1}(\frac{1sin30^0}{1.6} )\\\\ \theta = 18.21 ^0[/tex]
For contact lenses;
[tex]\rm n_1sin\theta = n_2 sin\theta_1 \\\\ \theta_1 = sin^{-1}\frac{1.6 \times sin 18.21^0}{1.4} \\\\ \theta_1 =20.92 ^0[/tex]
For fluid;
[tex]n_2 sin\theta_1 = n_2 sin \theta_3\\\\ \theta_3 = sin^{-1}\frac{1.4 sin 20.92^0}{1.3} \\\\ \theta_3 = 22.62 ^ 0 =23^0[/tex]
Hence the angle is the light traveling in the fluid will be 23⁰.
To learn more about snell's law refer to the link;
https://brainly.com/question/10112549
a stationary object experiences two forces as shown in the diagram below
Answer: the answer is B
Explanation: 80 is not the same as 150 so it will go the way 150 units of force is pulling.
Time Vs Position of Battery Operated Car what type of relationship is shown in the graph?
The work done is a vector quantity and SI base unit is J
Answer:
Is this your question? Also I think work done is a scalar quantity.
Explanation:
If a weather service map has a circle that
is shaded completely in, what does that
mean about the cloud cover in that area?
A. There is 100% cloud cover in that area.
B. There is 0% cloud cover in that area.
C. There is a good chance of rain.
D. There are sunny skies.
Answer:
A. There is 100% cloud cover in that area.
Explanation:
Cloud cover is recorded on weather charts by shading in parts of the circle.
If there are no clouds, the circle is left white and if the sky is completely covered in cloud, the circle is shaded completely in which means 100% cloud cover in that area.
Hydrocarbons are by-products of which of the following:
a. Fossil oils, mines and fossil fuels
b. Burning fires, water treatment plants and fossil oils
C. Combustion in fossil, lighting and exhaust fumes
d. Petrol, sea waves and combustion in vehicles
e. Burning fires and combustion in factories and vehicles
Answer:
A
Explanation:
Calculate the acceleration of a car if the force on the car is 450 Newtons and the mass is 1300 kilograms.
[tex] \Large {\underline { \sf {Required \; Solution :}}}[/tex]
We have ―
Force, F = 450 NMass of the car, m = 1300 kgWe have been asked to calculate the acceleration of the car.
[tex]\qquad \implies\boxed{\red{\sf{ F = ma }}}\\[/tex]
F denotes Forcem denotes massa denotes acceleration[tex] \quad \twoheadrightarrow\sf { 450 = 1300a} \\ [/tex]
[tex] \quad \twoheadrightarrow\sf {\cancel{ \dfrac{450}{1300}} = 1300a} \\ [/tex]
[tex]\quad\twoheadrightarrow\boxed{\red{\sf{0.346 \; ms^{-2} = a }}}\\[/tex]
Therefore, acceleration of the car is 0.346 m/s².
A 25.0kg girl pushes a 50.0kg boy so that he accelerates at 4.00m/s2. What is the force of the boy on the girl? A. 200N B. 100N C. 12.5 D. 400N
Answer:
a
Explanation:
so the answer is 200N
and I hope it is correct
What is the mass of a mallard duck whose speed is 9.1 m/s and whose momentum has a magnitude of 12 kg⋅m/s?
Answer:
m = 1.31 kg
Explanation:
Given that,
The speed of duck, v = 9.1 m/s
The magnitude of momentum, p = 12 kg-m/s
We need to find the mass of the duck. We know that the momentum of an object is given by :
p = mv
Where
m is the mass of the duck
[tex]m=\dfrac{p}{v}\\\\m=\dfrac{12\ kg-m/s}{9.1\ m/s}\\\\m=1.31 kg[/tex]
So, the mass of the duck is equal to 1.31 kg.
A uniform, 4.5 kg, square, solid wooden gate 2.0 m on each side hangs vertically from a frictionless pivot at the center of its upper edge. A 1.3 kg raven flying horizontally at 5.0 m/s flies into this door at its center and bounces back at 2.0 m/s in the opposite direction.
Required:
a. What is the angular speed of the gate just after it is struck by the unfortunate raven?
b. During the collision, why is the angular momentum conserved but not the linear momentum?
Answer:
its a. and jusing that youl
In the process of fluorescence, a molecule in its ground state will absorb a photon with a certain energy Eex, called the excitation energy, and then emit a photon with energy Eem, the emission energy. Obviously, the molecule cannot emit more energy than was absorbed.
a) You wrote in your notebook that you excited a fluorescent bead at λ = 640 nm and found that it fluoresced (emitted) at λ = 520 nm. Or was it the other way around? Do a calculation and see if those figures should be switched.
b) You shine a laser on your bead at the excitation wavelength. The laser has a power of 1 mW. How many photons are emitted by the laser in one second?
c) You wish to build a microscope that allows you to excite the bead at its excitation wavelength and detect the fluorescence at the emission wavelength. This requires a pair of filters, one that allows only the excitation wavelength to pass through, and the other that allows only the emission wavelength to pass through. What color will these filters appear (i.e. what color light will they transmit?) You may have to look at an electromagnetic spectrum to figure this out…
Answer:
a) the excitation energy is E₂ λ = 520 nm
the emission energy is E₁, λ= 640 nm
b) #_photons = 2.6 10¹⁸ photons,
c) he excitation wavelength λ = 520 nm is green, therefore the filter is also green
the emission wavelength is lam = 640 nm is orange
Explanation:
a) the energy of a photo is given by the planck relation
E = h f
the speed of light is
c = λ f
f = c /λ
we substitute
E = hc /λ
let's calculate the energy for the two photons
λ = 640 nm = 640 10⁻⁰ m
E₁ = 6.63 10⁻³⁴ 3 10⁸/640 10⁻⁹
E₁ = 3.1 10⁻¹⁹ J
λ = 520 nm = 520 10⁻⁹ m
E₂ = 6.63 10⁻³⁴ 3 10⁸/520 10⁻⁹
E₂ = 3.825 10⁻¹⁹ J
therefore the excitation energy is E₂ λ = 520 nm
the emission energy is E₁, λ= 640 nm
b) For this part let's use a direct proportion rule (rule of three). If a photon (lam = 520 nm) has an energy of 3.825 10⁻¹⁹ J, how many photons have an energy of E = 1 10-3 J. Remember that the power is the energy per unit of time
#_photons = 1 10⁻³ J (1 photon / 3.825 10⁻¹⁹ J)
#_photons = 2.6 10¹⁸ photons
c) the excitation wavelength λ = 520 nm is green, therefore the filter is also green
the emission wavelength is lam = 640 nm is orange