If there is a 1.0% minimum energy uncertainty in the photons, the pulse's minimum duration is 1.6313×10⁻¹⁴ seconds.
How do you calculate a photon's energy?There are two approaches to determine a photon's energy: E = h f can be used if the photon's frequency is known. This equation is referred to as Planck's equation because Max Planck proposed it. Using the formula E = h c, the photon's energy can be determined if its wavelength is known.
energy of the laser = h × c/λ
where h=Planck's constant-6.626×10⁻³⁴
c-speed of light = 3×10⁻⁸ m/s
λ = wavelength = 615 nm-615×10⁻⁹ m
energy = E = 6.626×10⁻³⁴×3×10⁸/(615×10⁻⁹) = 3.2322×10⁻¹⁹ J
then uncertainty in energy = 0.01×E = 3.2322×10⁻²¹ J
from Heisenberg uncertainty principle:
uncertainty in energy × uncertainty in time > h/(4× π)
==> uncertainty in time >6.626×10⁻³⁴/(4× π×3.2322×10⁻²¹)=1.6313×10⁻¹⁴
so minimum duration of the pulse is 1.6313×10⁻¹⁴ seconds.
To know more about If there is a 1.0% minimum energy uncertainty in the photons, the pulse's minimum duration is 1.6313×10⁻¹⁴ seconds.
How do you calculate a photon's energy?There are two approaches to determine a photon's energy: E = h f can be used if the photon's frequency is known. This equation is referred to as Planck's equation because Max Planck proposed it. Using the formula E = h c, the photon's energy can be determined if its wavelength is known.
energy of the laser=h × c/λ
where h=Planck's constant-6.626×10⁻³⁴
c-speed of light = 3×10⁻⁸ m/s
λ = wavelength = 615 nm-615×10⁻⁹ m
energy = E = 6.626×10⁻³⁴×3×10⁸/(615×10⁻⁹) = 3.2322×10⁻¹⁹ J
then uncertainty in energy = 0.01×E = 3.2322×10⁻²¹ J
from Heisenberg uncertainty principle:
uncertainty in energy × uncertainty in time > h/(4× π)
==> uncertainty in time >6.626×10⁻³⁴/(4× π×3.2322×10⁻²¹)=1.6313×10⁻¹⁴
so minimum duration of the pulse is 1.6313×10⁻¹⁴ seconds.
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an obstruction is just ahead on the shoulder. your front wheel leaves the roadway at high speed. when do you countersteer?
An obstruction is just ahead on the shoulder. Your front wheel leaves the roadway at a high speed. You countersteer when the front tire touches the roadway.
Countersteer is usually done by the cyclists and motorcyclists to turn at higher speeds. It is advisable to be done only on the race tracks. This is because the two wheels do not follow the same path during turning and it may affect other vehicles on normal roads. The rider must be leaned in the direction of turn in order to complete the turn. As the front wheel leaves at a higher speed, countersteering is done when the front wheel touches the ground.
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the moon orbits earth at an average distance of 3.84 x 108 m in a path that takes 27.3 days to complete. what is the centripetal acceleration of the moon? (remember, you must convert time into seconds.)
If the moon orbits the Earth at a distance of 3.84 x 10⁸ on a path that takes 27.3 days to complete, its centripetal acceleration will be 2.7x 10⁻³ m/s².
How can we determine the centripetal speed of the moon?A body moving in a circular path at a high rate of speed is said to be experiencing centripetal acceleration. We can calculate the moon's centripetal acceleration using the centripetal acceleration formula.
We are informed that the moon is approximately 3.84 x 10⁸ miles away from Earth and that a full rotation of the moon takes 27.3 days.
The distance traveled by the moon in 27.3 days is its velocity.
v = x/t
v = 2 πr/t
v = 2.41x10⁹/2.35x10⁶
v = 1025.5
The radius is 3.84 x 108 m and the velocity is 1,025.5 m/s. Here, we will determine the centripetal acceleration of the moon.
[tex]a_{c}[/tex] = v²/r
[tex]a_{c}[/tex] = (1025.5)²/3.84 x 10⁸
[tex]a_{c}[/tex] = 2.7 x 10⁻³
We now know the centripetal acceleration of the moon to be 2.7 103 m/s².
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what is the type of blood the contains antibody B and Rh
Answer:Blood type AB Rh+
Explanation:
how is cmb observed from earth
The Cosmic Microwave Background radiation, or CMB for squat, is a faint glow of light that fills the universe, falling on Earth from each direction with nearly uniform intensity.
How does CMB observe Earth?The CMB represents the heat leftover from the Big Bang. You can't see the CMB with your bare eye, but it is everywhere in the universe. It is unseen to humans because it is so cold, just 2.725 degrees above total zero. Planck mapped out the warp in the CMB due to gravitational lensing caused by dark matter's existence. The CMB materialized as an electromagnetic fog on optical telescopes and as a static hum on radio telescopes. The CMB will certainly emerge slightly different from any distant galaxy,
So we can conclude that The Cosmic Microwave Background (CMB) is the cooled remains of the first light that could ever travel freely throughout the Universe.
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How much gravitional potential energy would a 65.0kg rollerblader have at the top of a hill that is 45.0 meters high
Roller balder will have 28,665 J gravitational potential energy at the top of a hill that is 45.0 meters high
gravitation potential energy = m*g*h
mass = 65 kg
g = 9.8 [tex]m/s^{2}[/tex]
h = 45 m
gravitation potential energy = 65 * 9.8 * 45 = 28,665 J
Roller balder will have 28,665 J gravitational potential energy at the top of a hill that is 45.0 meters high
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a wire with a resistance of 6.0 () is drawn out through a die so that its new length is three times its original length. find the resistance of the longer wire, assuming that the resistivity and density of the material are not changed during the drawing process.
R0 is the original resistance. Thus, R = 9(6.0Ω) = 54 Ω.
Electric current flowing through and potential difference across an electrical component can be used to determine its resistance.
Ohm's Law, which depicts the connection between potential difference, current, and resistance:
V = I R, where V is the potential difference (in volts), V I is the current (in amps), A R is the resistance (in ohms), and
The following equation can be changed to determine the resistance:
R = V ÷ I
According to Ohm's equation, I = V/R, the behaviour of the material may be predicted if the resistance remains constant over a significant range of voltage. The definition above applies to both AC and DC applications of resistors, despite the fact that it deals with DC current and voltage.
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A student travels on a motorcycle and moves at a constant speed of 80 k/h for 15 m, determine the distance traveled in that time
Uniform line movement
Data:
V = 80km/h
T = 15m = 0.25 h
d = ?
We perform a conversion from minutes to hours.
15 m * 1 h/60 m = 0.25 h
The formula for uniform motion is:
V = d/t
We clear for distance:
d = v * t
d = 80 km/h * 0.25 h
d = 20 km
The distance traveled in that time is 20 km.
when a mass m1is placed on top of a spring and allowed to come to rest, the spring iscompressed by an amount x1. how much would the spring compress if it is an elevatoraccelerating upwards at 3g and has a mass of 4m1placed on top of the spring?a)16x1b)12x1c)4x1d)7x1e)8x
The spring compresses if it is an elevator accelerating upwards at 3g is Option A. a)16x
Acceleration is the rate of change of the velocity of an item with appreciation to time. Accelerations are vector portions. The orientation of an item's acceleration is given by the orientation of the net pressure appearing on that object.
Calculation:-
Gravitational acceleration = g
Spring constant of the spring = k
Mass of the first block = m1
Compression of the spring due to the first block = X1
m1g = kX1
Mass of the second block = 4m1
Upward acceleration of the elevator = 3g
The force from the spring on the second block = F
Compression of the spring due to the second block in the elevator = X2
From the free-body diagram of the 4m1 block,
(4m1)(3g) = F - 4m1g
F = 16m1g
kX2 = 16m1g
kX2 = 16(kX1)
X2 = 16X1
Compression of the spring due to a 4m1 block placed on it in an elevator accelerating upwards at 3g = 16X1.
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Gravity obeys an inverse square relation. This statement implies that the force due to gravity betweentwo massesa.will increase as the distance between the two masses increases.*b.will decrease as the square of the distance between the two masses increases.c.will cause the two masses to move away from each other.d.will cause the two masses to move in a straight line.e.will cause the two masses to orbit each other.
The inverse square relation implies that force resulting from gravity between two masses will decrease as the square of the distance between the two masses increases.
The force of gravity between any two objects is given by,
F = GM₁M₂/R²
Where,
M₁ and M₂ are the masses of the bodies.
R is the distance between them.
We know, if the masses are constant. then the force of gravity will be inversely proportional to the square of the distance between them.
This is what inverse square relation means here.
As the force of gravity and the square of the distance are inversely proportional to each other,
So, when the square of the distance between the masses increases, the force of gravity between the decreases.
Hence of all the options provided, b is the correc0,t which says, the force will decrease on increasing the inverse square of the distance.
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an automobile manufacturer claims that its product will travel 1.2 km in 20 s, starting from rest. what is the magnitude of the constant acceleration required to do this? answer in units of m/s 2 .
The amount of constant acceleration needed to accomplish this is:
6 m/s2.
What is constant acceleration?A velocity change that does not alter over time is referred to as a constant acceleration. A car's average acceleration remains steady at 20 mph per minute even if it increases its speed by 20 mph in one minute and another 20 mph the next.
Given;
The car will drive a distance of d = 1.2 km
To convert 1.2 km to m
1.2 x 1000
= 1200 m.
beginning speed of the car, where u = 0.
Travel time, t = 20 s
To get the constant acceleration, use the following kinematic equation;
d = ut + ¹/₂at²
1200 = 0 + ¹/₂(20)²a
1200 = 400 /2
1200 = 200a
a = 1200 / 200
a = 6 m/s²
Therefore, 6 m/s² of constant acceleration is needed to accomplish this.
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The amount of constant acceleration needed to accomplish this is 6 m/s2.
What is constant acceleration?A velocity change that does not alter over time is referred to as a constant acceleration. A car's average acceleration remains steady at 20 mph per minute even if it increases its speed by 20 mph in one minute and another 20 mph the next.
Given;
The car will drive a distance of d = 1.2 km
To convert 1.2 km to m
1.2 x 1000
= 1200 m.
beginning speed of the car, where u = 0.
Travel time, t = 20 s
To get the constant acceleration, use the following kinematic equation;
d = ut + ¹/₂at²
1200 = 0 + ¹/₂(20)²a
1200 = 400 /2
1200 = 200a
a = 1200 / 200
a = 6 m/s²
Therefore, 6 m/s² of constant acceleration is needed to accomplish this.
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a solid sphere has a radius of 0.200 m and a mass of 150 kg. how much work is required to get the sphere rolling with an angular speed of 50.0 rad/s on a horizontal surface? assume the sphere starts from rest and rolls witho
Work done on sphere is 10500 J.
Kinetic energy = 1/2 [tex]iw^{2}[/tex] + 1/2 [tex]m v^{2}[/tex]
I = 2/5 [tex]m R^{2}[/tex]
w = [tex]\frac{v}{r}[/tex]
Now, put these values in formula KE = 1/2 [tex]iw^{2}[/tex] + 1/2 [tex]m v^{2}[/tex]
KE = 10500 J
Now, by work energy theorem
Work done = 10500 - 0 = 10500 J
Hence, Work done on sphere is 10500 J.
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A van accelerates from a velocity of 2 m/s to a velocity of 20 m/s in 12 s.
Calculate the acceleration of the van.
Answer:
Explanation:
Given:
V₀ = 2 m/s
V = 20 m/s
Δt = 12 s
__________
a - ?
The acceleration of the van:
a = ΔV / Δt = (V - V₀) / Δt
a = (20 - 2) / 12 = 18 / 12 ≈ 1.5 m/s²
a funny car accelerates from rest through a measured track distance in time t with the engine operating at a constant power p. if the track crew can increase the engine power by a differential amount dp, what is the change in the time required for the run? (use any variable or symbol stated above as necessary.)
dT = -T^4/(2mD^2)dP
P = W/T = FD/T = (m a)D/T
dP = -maD/T^2 dT
dT = -T^2/(maD)dP
V = aT
D = 1/2 a T^2
a = 2D/T^2
dT = -T^4/(2mD^2)dP
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When a solid becomes a liquid, the particles
slip and slide past each other
are vibrating
are in a lattice structure
bounce off each other
solid particles vibrate and slip past each other when they become liquid.
what is the potential difference across a 19- m -long, 2.0- mm -diameter copper wire carrying an 7.6 a current?
The potential difference across a 19m long, 2.0mm diameter copper wire carrying a 7.6A current is 676 V.
The resistance of the wire is given by R = ρ L/A
where ρ is the resistivity of copper (ρ = 1.72E-8 Ωm) and L is the length of the wire (19m). So,
R = 1.72E-8 * 2.0E-3/7.6E3
= 912 Ω.
Assuming that no other circuit elements are present, the potential difference across this wire will be equal to the voltage drop across that resistor:
V = IR = 912 * 7.6E3
= 676 V
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monochromatic light from a distant source is incident on a slit 0.75 mm wide. on screen 2 m away, the distance from the central maximum of the diffraction pattern to the first minimum is measured to be 1.35 mm. find the wavelength of the light.
Displacement from the center line for minimum intensity is 1.35 mm , width of the slit is 0.75 so Wavelength of the light is 506.25.
How to find Wavelength of the light?When a wave is bent by an obstruction whose dimensions are similar to the wavelength, diffraction is observed. We can disregard the effects of extremes because the Fraunhofer diffraction is the most straightforward scenario and the obstacle is a long, narrow slit.
This is a straightforward situation in which we can apply the
Fraunhofer single slit diffraction equation:
y = mλD/a
Where:
y = Displacement from the center line for minimum intensity = 1.35 mm
λ = wavelength of the light.
D = distance
a = width of the slit = 0.75
m = order number = 1
Solving for λ
λ = y + a/ mD
Changing the information that the issue has provided:
λ = 1.35 * 10^-3 + 0.75 * 10^-3 / 1*2
=5.0625 *10^-7 = 506.25
so
Wavelength of the light 506.25.
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How can gravity's role in tectonic plate motion be described? question 6 options: earth's magnetic field reverses ridge push and slab pull circulating material in the mantle earth's internal heating
Gravity's role in the tectonic plate motion can be described on the basis of ridge push and slab pull of tectonic plates.
What are ridge push and slab pull?Ridge push refers to gravitational sliding. It is a driving force for plate motion in plate tectonics, occurring at mid-ocean ridges as the result of the rigid lithosphere sliding down the hot and raised asthenosphere below mid-ocean ridges.
Slab pull is a pulling force that is exerted by a cold and dense oceanic plate plunging into the mantle. The term for the process of a tectonic plate descending into the mantle is subduction. Subduction may emerge due to gravity.
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Substances in a(n)________
separate properties.
keep their separate properties, but in a(n)___________
the parts are bonded and do not keep their
Substances in a mixture keep their separate properties, but in a compound the parts are bonded and do not keep their separate properties.
Mixtures contains elements and compounds without any fixed ratio and not by any means of chemical bonds. The elements and compounds are physically mixed and so they will be visibly distinct.
Compounds contains elements in a fixed ratio and is connected by chemical bonds. They only contain one type of molecule. Since they are chemically combined the particles appear as one and is not visibly distinct.
Therefore, substances in a mixture keep their separate properties, but in a compound the parts are bonded and do not keep their separate properties.
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which answer would you choose if the rocks fall out through a hole in the floor of the car, one at a time?
The car speeds remains constant.
Using the following equation for momentum:
Pi=Pf
(c=car and r=rock)
McVc + MrVr = McV'c + MrV'r
Initially
Vc=Vr=Vi
and since rocks are being dropped directly downward, final momentum of the rocks (being dropped one at a time) should be zero because their falling down, out of the railroad car.
So:
Vi( Mc+Mr) = McV'c V'c = [Vi(Mr+Mc)] / Mc
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a lighthouse is located on a small island 5 km away from the nearest point p on a straight shoreline and its light makes eight revolutions per minute. how fast (in km/min) is the beam of light moving along the shoreline when it is 1 km from p? (round your answer to one decimal place.)
The movement of the beam of light is an illustration of distance and rates
The beam of light along the shoreline is moving at 261.5 km per minute when it is 1 km from P
What is rate of change of distance?The ratio of the distance traveled to the time required is used to compute average speed, which is the rate at which distance changes in relation to time.
[tex]\frac{d\theta}{dt}[/tex] = 8 rev min⁻¹ = 16 [tex]\pi[/tex] rad min⁻¹
tan [tex]\theta[/tex] = [tex]\frac{x}{5}[/tex]
Differentiate both sides with respect to t
[tex]sec^2 (\theta) \frac{d\theta}{dt} = \frac{1}{5} \frac{dx}{dt}[/tex]
[tex]\frac{d\theta}{dt}[/tex] = 16 [tex]\pi[/tex]
Then,
[tex]\frac{dx}{dt}[/tex] = [tex]sec^2 (\theta) X 80\pi[/tex]
From the question, x = 1. calculate the hypotenuse (h) side of the triangle, using the following Pythagoras theorem.
[tex]h^2 = 1+ 5^2\\[/tex]
h =[tex]\sqrt{26}[/tex]
sec ([tex]\theta[/tex]) = [tex]\frac{\sqrt{26} }{5}[/tex]
Substitute sec ([tex]\theta[/tex]) = [tex]\frac{\sqrt{26} }{5}[/tex] in [tex]\frac{dx}{dt}[/tex] = [tex]sec^2 (\theta) X 80\pi[/tex].
[tex]\frac{dx}{dt} = (\frac{\sqrt{26} }{5} )^2 . 80\pi[/tex]
= 83.2 [tex]\pi[/tex] = 261.48
Hence, the beam of light along the shoreline is moving at 261.5 km per minute when it is 1 km from P.
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two wheels, a and b, are both shaped like uniform disks and have the same overall mass, but wheel a has twice the radius of wheel b. how do we calculate the moments of inertia (around the axis of symmetry) for each wheel?
The ratio of I sub A to I sub B is 4.
How can you calculate the ratio of A to B?
A/B would be your formula if you were comparing one data point (A) to another data point (B). This indicates that you are multiplying information A by information B. For instance, your ratio will be 5/10 if A is 5 and B is 10. How do we determine each wheel's moments of inertia (around the axis of symmetry) I is equal to 1 over 2 times m times R squared is used to compute the moments of inertia for both masses and radii. We simply use a common factor to cancel. So 4:2=2:1 . The simplest representation of the ratio 4 to 2 is the ratio 2 to 1. Additionally, since each pair of numbers has the same relationship, the ratios are equivalent.
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lorry is moving with a uniform acceleration of 1.5ms2 .at a certain time it is travelling at a spedd of 6ms .calculate the speed of the lorry 4s later
The speed of the lorry 4 seconds later, given it was moving with uniform acceleration of 1.5 m/s² is 12 m/s
How do I determine the final speed of the lorry?We'll begin by listing out the various parameters obtained from the question. This is shown below:
Acceleration (a) = 1.5 m/s²Initial speed (u) = 6 m/sTime (t) = 4 secondsFinal speed (v) =?The final speed of the lorry can be obtained as follow:
a = (v - u) / t
1.5 = (v - 6) / 4
Cross multiply
v - 6 = 1.5 × 4
v - 6 = 6
Collect like terms
v = 6 + 6
v = 12 m/s
Thus, from the calculation made above, the final speed of the lorry is 12 m/s
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A person rides in an elevator.
What is the equal and opposite force for the force of the elevator floor pushing up on the person as described by Newton's third law?
The equal and opposite force for the force of the elevator floor pushing up on the person as described by Newton's third law is the weight and the reaction force from its effect.
What is an Elevator?This is referred to as a device which is used in the vertical transportation of goods and people among the floors in a buildings.
When an individual steps into the elevator, the weight acts on it and it is known as a downward force while the reaction acts upward in an opposite reaction as described by Newton's third law in this scenario.
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Pls help answer this
Answer: The rods both have the same charge therefore they repel each other. The force of repulsion creates a downward force on the balance pan and therefore the balance registers a higher reading.
The graph shows distance versus time for an object.
Which of the following correctly describes the object's motion?
The object is moving with increasing acceleration.
The object is moving with constant acceleration.
The object is moving with increasing velocity.
The object is moving with constant velocity.
The velocity of an object is the ratio of distance to the time. The graph shows, an increase in distance with the increase in time. This linearity make the velocity constant. Hence, the option D is correct.
What is velocity?Velocity of a substance is the measure of distance travelled per unit time. Thus it is the ratio of distance to time.In physics, velocity is the rate of speed.
Velocity = distance/time.
Hence, as the time taken for the travel increases velocity will decreases. In the given graph at each point distance shows linear relation with the time and it obtains a straight line.
Therefore, the distance is increasing with increase in time means the velocity is not changing and it remains constant. Hence, option D is correct.
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a playground merry-go-round has a mass of 120 kg and a radius of 1.80 m and it is rotating with an angular velocity of 0.350 rev/s. what is its angular velocity (in rev/s) after a 15.0 kg child gets onto it by grabbing its outer edge? the child is initially at rest.
Angular velocity (in rev/s) after a 15.0 kg child gets onto it by grabbing its outer edge is 1.575 rad/s.
The angular velocity of the merry-go-round after a child gets on it is equal to the angular velocity of the child plus the angular velocity of the merry-go-round.
The angular velocity of a rotating object can be calculated using a formula:
ω = ω + (m/r)
where ω is the original angular velocity, m is the mass of an object that's been added to it, r is its radius, and (m/r) is the change in mass divided by its radius. When we plug in our values for this problem, we get:
ω = 0.350 rad/s + ((15 kg)/(1.8 m)) rad/s
= 0.350 rad/s + 1.25 rad/s
= 1.575 rad/s
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if you swing a bucket of water fast enough in a vertical circle, at the highest point the water does not spill out because an outward force balances the pull of gravity on the water. if you swing a bucket of water fast enough in a vertical circle, at the highest point the water does not spill out because an outward force balances the pull of gravity on the water. true false
We must understand both inertia and gravity to find a solution.
What is inertia?
The matter has an attribute called inertia that makes it resist changes in velocity (speed and direction). Newton's first law of motion states that an object moving at a certain speed will stay there unless an outside force acts upon it.
What is gravity?
A planet or other body's gravitational field pulls objects toward its center. The force of gravity is what keeps every planet in its orbit around the sun.
A vertical circle spun while holding a bucket full of water prevents the water from spilling out due to inertia.
Keep the bucket in place as the water tries to fly off.
Therefore we can conclude that it is false.
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what is the point in the sky directly overhead called? which constellation is closest to this point tonight?
The answers include the following:
The point in the sky which is directly overhead is called Zenith.The constellation which is closest to this point tonight is Polaris.What is Constellation?This is referred to as a group of stars that form a perceived pattern or outline and are usually given names and an example is hydra.
The Zenith as the name implies is known as the overhead point in the sky which is usually hardly seen while the constellation which is closest to this point tonight is Polaris due to the position thereby making it the most appropriate choice.
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Which statement best describes heat?
A. Heat flows from cold to hot and is a form of thermal energy.
B. Heat flows from hot to cold and is the transfer of thermal energy.
C. Heat flows from hot to cold and is a form of thermal energy.
D. Heat flows from cold to hot and is the transfer of thermal energy.
Answer: D
Explanation:
Salem, Sabrina’s magical black cat, gets scared and jumps straight upward with an initial velocity of 20 m/s from a height of 115-meters.
Draw a velocity vs time graph to describe the cat’s motion for the first five seconds of motion.
What is the cat’s velocity and acceleration at it’s maximum height?
What is the cat’s velocity when it hits the ground?
How long does it take for the cat to hit the ground?
PLS HELP!!!!!
Considering a quadratic equation to model the height of the car, we have that:
The graph is given at the end of the answer.At the maximum height, the velocity is of zero and the acceleration is of -9.8 m/s².The velocity when the cat hits the ground is: -51.54 m/s.It takes 7.30 seconds for the cat to hit the ground.What is the quadratic equation for a projectile's height?Considering an acceleration = gravity of -9.8m/s², the equation for the height is given as follows:
h(t) = -4.9t² + v(0)t + h(0).
In which:
v(0) is the initial speed.h(0) is the initial height.Considering the values of these parameters for this problem, of v(0) = 20, h(0) = 115, the equation is:
h(t) = -4.9t² + 20t + 115.
At the maximum height point, we have that:
The velocity is of zero. (standard)The acceleration if of -9.8 m/s². (standard).The velocity function is:
v(t) = v(0) - gt
v(t) = 20 - 9.8t.
Which is the linear function graphed at the end of the answer.
The cat hits the ground at t > 0 for which h(t) = 0, hence:
-4.9t² + 20t + 115 = 0.
Which is a quadratic equation with coefficients given by:
a = -4.9, b = 20, c = 115.
Using a calculator, the positive solution for this equation is:
t = 7.30s.
At this instant, the velocity is:
v(t) = 20 - 9.8(7.3) = -51.54 m/s.
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