Answer:
Waves carry energy from one place to another.
Explanation:
Because waves carry energy, some waves are used for communication, eg radio and television waves and mobile telephone signals.
has been proposed to use an array of infrared telescopes spread over thousands of kilometers of spaceto observe planets orbiting other stars. Consider such an array with an effective diameter of 6000 km, whichobserves infrared radiation at a wavelength of 10m. If it is used to observe a planet orbiting the star 70Virginis, which is 59 light years from our solar system, what is the size of the smallest details that the arraymight resolve on the planet
Answer:
[tex]\triangle x=1.135 *10^9km[/tex]
Explanation:
From the question we are told that:
Diameter of array[tex]d=6000km \approx 6000*10^3[/tex]
Infrared wavelength [tex]\lambda =10m[/tex]
Distance of planet [tex]d=59 light\ years \approx 55.82*10^{16}m[/tex]
Generally the equation for Diffraction is mathematically given by
[tex]sin\theta =1.22\frac{\lambda}{D}[/tex]
Given that
[tex]sin\theta=\frac{\triangle x}{R}[/tex]
Therefore
[tex]\frac{\triangle x}{R}=1.22\frac{\lambda}{D}[/tex]
[tex]\triangle x=1.22\frac{R \lambda}{D}[/tex]
[tex]\triangle x=1.22\frac{10 *55.82*10^{16}}{6000*10^3}[/tex]
[tex]\triangle x=1.135 *!0^1^2m[/tex]
[tex]\triangle x=1.135 *10^9km[/tex]
A 1.10 kg block is attached to a spring with spring constant 17 N/m. While the block is sitting at rest, a student hits it with a hammer and almost instantaneously gives it a speed of 46 cm/s.
A) What is the amplitude of the subsequent oscillations?
B) What is the block's speed at the point where x = 0.25 A?
Answer:
Explanation:
The kinetic energy of block will be converted into potential energy of spring .
If A be the amplitude of oscillations
1 /2 k A² = 1/2 m v²
17 A² = 1.1 x .46²
A² = .0137
A= 11.7 cm
B )
when x = .25 A = .25 x 11.7 = 2.9 cm
potential energy = 1/2 k x²
= .5 x 17 x ( .029 )² = .00715 J
kinetic energy = 1/2 m v²
1/2 m v² + .00715 = .5 1.1 x .46²
1/2 m v² + .00715 = .1164
1/2 m v² = .10925
.5 x 1.1 x v²= .10925
v² = .1986
v = .4456 m /s
= 44.56 cm /s
Star X has an apparent magnitude of 1. Star Y has an apparent magnitude of 4. Both stars are in the same star cluster. Which star is more intrinsically luminous and by what factor
Answer:
Explanation:
From the given information:
Since both stars are in the same cluster, the magnitude and luminosity relationship can be calculated as:
[tex]m_1 - m_2 = -2.5 log _{10} (\dfrac{L_1}{L_2})[/tex]
Given that;
m_1 = 1 and
m_2 = 4
Therefore,
[tex]1 - 4 = -2.5 log _{10} ( \dfrac{L_1}{L_2})[/tex]
[tex]3 = -2.5 log _{10} ( \dfrac{L_1}{L_2})[/tex]
Making [tex]\dfrac{L_1}{L_2}[/tex] the subject of the formula:
[tex]\implies \dfrac{L_1}{L_2}= 10^{(\dfrac{3}{2.5})}[/tex]
=15.84
≅ 16
Hence, we can conclude that star X is more luminous by a factor of 16
A car is travelling at 27m/s and decelerates at a=5m/s2 for a distance of 10m. Calculate its final velocity. (Hint does deceleration imply that the acceleration is positive or negative?)[
Answer:
use the formula to calculate acceleration and you'll get the answers
In medieval times it was believed that projectiles were pushed through the air until they reached their impetus.
a. True
b. Fals
Answer:
false
Explanation:
If acceleration is zero what statement about velocity is
true *
A)Velocity is zero
B)Velocity is constant
C)Velocity cannot be determined
D) Velocity is changing
Answer: A
Velocity is zero because the acceleration isn't affected, and velocity is the rate of change, so it can't be any other options.
Answer:
B)Velocity is constantExplanation:
If an object moves with a velocity and there is no acceleration, then the velocity remains constant. His velocity after five second will be equal to his initial velocity.#keeplearning dude:)2. A 4kg object possesses 18J of Kinetic energy. What is the velocity?
Plz help I’ll give you points!
A device known as an optical resonator is used in lasers. An optical resonator consists of an arrangement of mirrors that reflect electromagnetic radiation back and forth within an empty cavity. The electromagnetic radiation within the cavity reflects off of the mirrors multiple times. The mirrors are precisely placed so that only particular frequencies can survive within the cavity via constructive interference. All other frequencies are suppressed via destructive interference. The end result is a beam of light of a certain frequency.
An optical resonator of the type described above depends on the tendency of light to
A. behave as a wave.
B. excite atoms to certain energy levels.
C. excite electrons to certain energy levels.
D. behave as a particle.
Answer:
A. The resonator behaves as a wave guide (a hollow pipe used as a transmission line). The characteristics of the pipe depend on the type of the wave to be transmitted.
Think of a hydropower dam . How is electrical energy produced from potential and kinetic energy ?
hydroelectric dam converts the potential energy stored in a water reservoir behind a dam to mechanical energy—mechanical energy is also known as kinetic energy. ... The generator converts the turbine's mechanical energy into electricity.
Hope this helps!
Answer:
Potential energy and kinetic energy are constituents of mechanical energy.
When a turbine is switched on, it rotates with mechanical energy.
Since a motor runs the turbine, it converts this mechanical energy to electrical energy.
0)
A-B-C-D-E
Describe the mass of the reactants and products given the balanced chemical reaction
A)
The mass of the products is 2/3 that of the reactants.
B)
The mass of the reactants equals the mass of the products.
C)
The mass of the reactants is less than the mass of the products.
D)
The mass of the reactants is greater than the mass of the products.
Answer:
D)
The mass of the reactants is greater than the mass of the products.
A 6kg object undergoes an acceleration of 2m/s, what is the magnitude of the resultant acting on it . If this same force is applied to a 4kg object, what acceleration is produced
Answer:
[tex]12\; \rm N[/tex].
[tex]3\; \rm m\cdot s^{-2}[/tex].
Explanation:
By Newton's Second Law, the acceleration of an object is proportional to the size of the resultant force on it, and inversely proportional to the mass of this object.
[tex]\displaystyle \text{acceleration} = \frac{\text{resultant force}}{\text{mass}}[/tex].
Rearrange this equation for the resultant force on the object:
[tex]\text{resultant force} = \text{acceleration} \cdot \text{mass}[/tex].
For the [tex]6\; \rm kg[/tex] object in this question:
[tex]\begin{aligned} F &= m \cdot a \\ &= 6\; \rm kg \times 2\; \rm m \cdot s^{-2} \\ &=12\; \rm N\end{aligned}[/tex].
When the resultant force on the [tex]4\; \rm kg[/tex] object is also [tex]12\; \rm N[/tex], the acceleration of that object would be:
[tex]\begin{aligned} a &= \frac{F}{m} \\ &= \frac{12\; \rm N}{4\; \rm kg} = 3\; \rm m \cdot s^{-2}\end{aligned}[/tex].
The classical theory of electromagnetism predicted that the energy of the electrons ejected should have been proportional to the intensity of the light.
a. True
b. False
Answer:
False
Explanation:
No, it is not true that energy of the electrons ejected should have been proportional to the intensity of the light. Perhaps the kinetic energy of the ejected electrons is independent of the intensity of the incident radiation. This is the very fact that classical theory of electromagnetism fails to explain in photoelectric effect. The kinetic energy of the electrons remains constant even if the amplitude of the incident light is increased.
A coil of resistance 100ohm is placed in a magnetic field of 1mWb the coil has 100 turns and a galvanometer of 400ohm resistance is connected in series with it. find the average emf and the current if the coil is moved in one tenth of a second from the given field to a field of 2.0mWb
Answer:
C
Explanation:
C
Extra CreditA particle is directed along the axis of the instrument in the gure. Aparallel plate capacitor sets up an electric eld E, which is orientedperpendicular to a uniform magnetic eld B. If the plates are separated byd= 2:0 mm and the value of the magnetic eld isB= 0:60T. Calculatethe potential di erence, between the capacitor plates, required to allow aparticle
This question is incomplete, the complete question is;
A particle is directed along the axis of the instrument in the figure below. A parallel plate capacitor sets up an electric field E, which is oriented perpendicular to a uniform magnetic field B. If the plates are separated by d = 2.0 mm and the value of the magnetic field is B = 0.60T.
Calculate the potential difference, between the capacitor plates, required to allow a particle with speed v = 5.0 × 10⁵ m/s to pass straight through without deflection.
Hint : ΔV = Ed
Answer:
the required potential difference, between the capacitor plates is 600 V
Explanation:
Given the data in the question;
B = 0.60 T
d = 2.0 mm = 0.002 m
v = 5.0 × 10⁵ m/s.
since particle pass straight through without deflection.
F[tex]_{net[/tex] = 0
so, F[tex]_E[/tex] = F[tex]_B[/tex]
qE = qvB
divide both sides by q
E = vB
we substitute
E = (5.0 × 10⁵) × 0.6
E = 300000 N/C
given that; potential difference ΔV = Ed
we substitute
ΔV = 300000 × 0.002
ΔV = 600 V
Therefore, the required potential difference, between the capacitor plates is 600 V
HURRY IM TIMED!
The age and gender of an audience are important to consider when deciding on a subject.
True
False
Answer:
True.
Explanation:
true
knowing your audience there General age gender education level religion language culture and gave group members is the single most important aspect of developing your speech this means the speaker dock smart the audience wasn't often without asking question or spending with any feedback
Question 5 of 10
The graph below shows the downloads of two songs over time.
70
Song 1
60
50
40
Number of downloads
(spopunu)
Song 2
30
20
10
O
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Time (minutes)
Which term describes the slope of the graph of song 2 between minute 6 and
minute 7?
A. Positive
B. Zero
C. It is impossible to calculate
D. Negative
SUBMIT
Answer:
b
Explanation:
What is the flux through the plane taken parnllel to the field?
Answer:
the flux through the plane is zero.
Explanation:
which of the following best defines spring constant ?
a. the amount of force needed to extend or compression of a spring for every 1 kilogram of the spring.
b. the amount of force needed every 1 meter of stretch or compression of the spring.
c. the amount of energy needed to extend or compress a spring for every 1 kilogram of mass of the spring.
d. the amount of energy needed for every 1 meter of stretch or compression of the spring.
Answer:
your answer gonna be The letter C is the correct answer
A winch is capable of hauling a ton of bricks vertically two stories (6.35 m ) in 24.5 s .
If the winch’s motor is rated at 5.80 hp , determine its efficiency during raising the load.
Answer: 84 %
Explanation:
1. A train is moving north at 5 m/s on a straight track. The engine is causing it to accelerate northward at 2 m/s^2.
How far will it go before it is moving at 20 m/s?
A) 83
B) 43
C) 39
D) 94
E) 20
Answer:
It will go up to 93.75 m before it is moving at 20 m/s
Explanation:
As we know that
[tex]v^2 - u^2 = 2aS[/tex]
here v is the final speed i.e 20 m/s
u is the initial speed i.e 5 m/s
a is the acceleration due to gravity i.e 2 m/s^2
Substituting the given values in above equation, we get -
[tex]20^2 - 5^2 = 2*2*S\\S = 93.75[/tex]meters
A truck is traveling on a level road. The driver suddenly applies the brakes, causing the truck to decelerate by an amount g/2. This causes a box in the rear of the truck to slide forward. If the coefficient of sliding friction between the box and the truckbed is 2/5, find the acceleration of the box relative to the truck and relative to the road.
Answer:
Truck [tex]\dfrac{g}{10}[/tex]
Road [tex]-\dfrac{g}{10}[/tex]
Explanation:
[tex]a_1[/tex] = Acceleration of truck = [tex]-\dfrac{g}{2}[/tex]
[tex]\mu[/tex] = Coefficient of friction = [tex]\dfrac{2}{5}[/tex]
Frictional force is given by
[tex]f=-\mu mg\\\Rightarrow f=-\dfrac{2}{5}mg\\\Rightarrow ma_2=-\dfrac{2}{5}mg\\\Rightarrow a_2=-\dfrac{2}{5}g[/tex]
Net acceleration is given by
[tex]a=a_2-a_1\\\Rightarrow a=-\dfrac{2}{5}g+\dfrac{g}{2}\\\Rightarrow a=\dfrac{g}{10}[/tex]
The acceleration of the box relative to the truck is [tex]\dfrac{g}{10}[/tex] and [tex]-\dfrac{g}{10}[/tex] relative to the road.
A community plans to build a facility to convert solar radiation to electrical power. The community requires 2.20 MW of power, and the system to be installed has an efficiency of 30.0% (that is, 30.0% of the solar energy incident on the surface is converted to useful energy that can power the community). Assuming sunlight has a constant intensity of 1 020 W/m2, what must be the effective area of a perfectly absorbing surface used in such an installation
Answer:
The answer is "[tex]\bold{7.18 \times 10^3 \ m^2}[/tex]".
Explanation:
The efficiency system:
[tex]\eta =\frac{P_{req}}{P} \times 10\\\\P =\frac{P_{req}}{\eta} \times 10\\\\[/tex]
[tex]=(\frac{2.20 \times 10^6 \ W}{30})\times 100\\\\=(\frac{220 \times 10^6 \ W}{30})\\\\=(\frac{22 \times 10^6 \ W}{3})\\\\=7.33 \times 10^6 \ W[/tex]
Using formula:
[tex]A=\frac{P}{I}[/tex]
Effective area:
[tex]A= \frac{7.33 \times 10^6 \ W}{1020\ \frac{W}{m^2}}\\\\[/tex]
[tex]=\frac{7.33 \times 10^6 }{1020}\ m^2 \\\\ =0.0071862 \times 10^6 \ m^2 \\\\=7.1862 \times 10^3 \ m^2 \\\\[/tex]
Which of the following is not a unit of speed *
a) m/s
b) km/s
c) mph [miles per hour]
d) light year
Answer:
I think it's light year but there shouldn't be also km/s but km/h
A nuclear power plant generates a total of 3 GW of power at an efficiency of 33%. The nuclear reactor has a recoverable energy per fission of 210 MeV. Approximately 65% of the plant's power comes from fissions in 235U, the remainder from fissions in plutonium, 239Pu. calculate: (a) the net electric power output, (b) the rate of fission events (per second) in the reactor core, (c) the mass of 235U used up in one year (hint: every fission event consumes one 235U nucleus and in the reactor core about 1.0 (1020) nuclei of U 235 are consumed every second. (d) If the plant were operated at full power for 1 year, how many
Answer:
Explanation:
From the question we are told that:
Plant Generates [tex]P=3GW[/tex]
Efficiency [tex]\eta =33\%[/tex]
Recoverable energy per fission [tex]\mu=210MeV \approx 336.42*18^{-7}J[/tex]
Fission Power [tex]F_p=235U[/tex] [tex](65\% of Plant\ power)[/tex]
Fission in plutonium [tex]F_{pl}=239Pu[/tex]
a)
Generally the equation for net electric power output [tex]P_o[/tex] is mathematically given by
[tex]P_o=P*\frac{1}{\eta}[/tex]
[tex]P_o=3*\frac{100}{3}[/tex]
[tex]P_o=9.0GW[/tex]
b)
Generally the equation for Rate of Fission [tex]F_{rate}[/tex] is mathematically given by
[tex]F_{rate}=\frac{P_o}{\mu}}[/tex]
[tex]F_{rate}=\frac{9*10^{9}}{336.42*18^{-7}}}[/tex]
[tex]F_{rate}=27.02*10^{13}[/tex]
c)
Generally the equation for Mass of [tex]^{235} U[/tex] used in a yr [tex]M_{U/yr}[/tex] is mathematically given by
[tex]M_{U/yr}=P_o*\frac{65}{100}[/tex]
[tex]M_{U/yr}=5.91GW[/tex]
A block of weight 1200N is on an incline plane of 30° with the horizontal, a force P is applied to the body parallel to the plane, if the coefficient of the static friction is 0.20 and kinetic friction is 0.15 (1) find the value of P to cause motion up the plane (2) find P to prevent motion down the plane. (3) Find P to cause continuous motion up the plane.
Answer:
a) P = 807.85 N, b) P = 392.15 N, c) P = 444.12 N
Explanation:
For this exercise, let's use Newton's second law, let's set a reference frame with the x-axis parallel to the plane and the direction rising as positive, and the y-axis perpendicular to the plane.
Let's use trigonometry to break down the weight
sin θ = Wₓ / W
cos θ = W_y / W
Wₓ = W sin θ
W_y = W cos θ
Wₓ = 1200 sin 30 = 600 N
W_y = 1200 cos 30 = 1039.23 N
Y axis
N- W_y = 0
N = W_y = 1039.23 N
Remember that the friction force always opposes the movement
a) in this case, the system will begin to move upwards, which is why friction is static
P -Wₓ -fr = 0
P = Wₓ + fr
as the system is moving the friction coefficient is dynamic
fr = μ N
fr = 0.20 1039.23
fr = 207.85 N
we substitute
P = 600+ 207.85
P = 807.85 N
b) to avoid downward movement implies that the system is stopped, therefore the friction coefficient is static
P + fr -Wx = 0
fr = μ N
fr = 0.20 1039.23
fr = 207.85 N
we substitute
P = Wₓ -fr
P = 600 - 207,846
P = 392.15 N
c) as the movement is continuous, the friction coefficient is dynamic
P - Wₓ + fr = 0
P = Wₓ - fr
fr = 0.15 1039.23
fr = 155.88 N
P = 600 - 155.88
P = 444.12 N
A TMS (transcranial magnetic stimulation) device creates very rapidly changing magnetic fields. The field near a typical pulsed-field machine rises from 0 T to 2.5 T in 200 μs . Suppose a technician holds his hand near the device so that the axis of his 2.0-cm-diameter wedding band is parallel to the field.
Part A
What emf is induced in the ring as the field changes?
Express your answer to two significant figures and include the appropriate units.
ε = ___________
Part B
If the band is gold with a cross-section area of 4.0 mm2, what is the induced current? Assume the band is of jeweler's gold and its resistivity is 13.2 x 1010 Ω*m.
Express your answer to two significant figures and include the appropriate units.
I = ____________
Answer:
A. 3.9 V B. 1.9 fA
Explanation:
Part A
What emf is induced in the ring as the field changes?
Express your answer to two significant figures and include the appropriate units.
The induced emf ε = ΔΦ/Δt where ΔΦ = change in magnetic flux = ΔABcosθ where A = area of coil and B = magnetic field strength, θ = angle between A and B = 0 (since the axis of the ring is parallel )Δt = change in time
ε = ΔΦ/Δt
ε = ΔABcos0°/Δt
ε = AΔB/Δt
A = πd²/4 where d = diameter of ring = 2.0 cm = 2.0 × 10⁻² m, A = π(2.0 × 10⁻² m)²/4 = π4.0 × 10⁻⁴ m²/4 = 3.142 × 10⁻⁴ m², ΔB = change in magnetic field strength = B₁ - B₀ where B₁ = final magnetic field strength = 2.5 T and B₀ = initial magnetic field strength = 0 T. ΔB = B₁ - B₀ = 2.5 T -0 T = 2.5 T and Δt = 200 μs = 200 × 10⁻⁶ s.
So, ε = AΔB/Δt
ε = 3.142 × 10⁻⁴ m² × 2.5 T/200 × 10⁻⁶ s
ε = 7.854 × 10⁻⁴ m²-T/2 × 10⁻⁴ s
ε = 3.926 V
ε ≅ 3.9 V
Part B
If the band is gold with a cross-section area of 4.0 mm2, what is the induced current? Assume the band is of jeweler's gold and its resistivity is 13.2 x 1010 Ω*m.
Express your answer to two significant figures and include the appropriate units.
Since current, i = ε/R where ε = induced emf = 3.926 V and R = resistance of band = ρl/A where ρ = resistivity of band = 13.2 × 10¹⁰ Ωm, l = length of band = πd where d = diameter of band = 2.0 cm = 2.0 × 10⁻² m. So, l = π2.0 × 10⁻² m = 6.283 × 10⁻² m and A = cross-sectional area of band = 4.0 mm² = 4.0 × 10⁻⁶ m².
So, i = ε/R
= ε/ρl/A
= εA/ρl
= 3.926 V × 4.0 × 10⁻⁶ m²/(13.2 × 10¹⁰ Ωm × 6.283 × 10⁻² m)
= 15.704 × 10⁻⁶ V-m²/(82.9356 × 10⁸ Ωm²
= 0.1894 × 10⁻¹⁴ A
= 1.894 × 10⁻¹⁵ A
≅ 1.9 fA
compute the distance and displacment of the puppy using visual analysis of the diagram?
Answer:
Distance A:11km
B:10km
Explanation:
Displacement A and B is 9km
6. If an object accelerates at 3m/s/s, how long does it take for the object to travel at a speed of 12 m/s.
Answer:
4 seconds
Explanation:
Assuming that the object started from rest,
v = at
--> t = v/a = (12 m/s) / (3 m/s^2)
= 4 seconds
How long will it take you to drive, at 80km/h a distance of 275km?
Answer:
3.44 s
Explanation:
speed=distance/time
=>t = s/v
=> t = 275/80
= 3.437.. s
Plutonium-238 has a half life of 87.7 years. What percentage of a 5 kilogram (kg) sample remains after 50 years?
Answer:
i dont know but i should know try g o o g l e
Explanation: