Answer:
2577 K
Explanation:
Power radiated , P = σεAT⁴ where σ = Stefan-Boltzmann constant = 5.6704 × 10⁻⁸ W/m²K⁴, ε = emissivity of bulb filament = 0.8, A = surface area of bulb = 30 mm² = 30 × 10⁻⁶ m² and T = operating temperature of filament.
So, T = ⁴√(P/σεA)
Since P = 60 W, we substitute the vales of the variables into T. So,
T = ⁴√(P/σεA)
= ⁴√(60 W/(5.6704 × 10⁻⁸ W/m²K⁴ × 0.8 × 30 × 10⁻⁶ m²)
= ⁴√(60 W/(136.0896 × 10⁻¹⁴ W/K⁴)
= ⁴√(60 W/(13608.96 × 10⁻¹⁶ W/K⁴)
= ⁴√(0.00441 × 10¹⁶K⁴)
= 0.2577 × 10⁴ K
= 2577 K
A ratio is another name for a decimal true or false
Surface currents are on the
of the Earth's oceans
what is the direction of the third force that would cause the box to remain stationary on the ramp ?
An arrow pointing from the bottom of the ramp to the top, I assume it would be friction.
Derive an expression for Root Mean Square (RMS) cur-rent through the capacitor as a function of the applied voltage amplitude. Recall that the RMS value of a sinewave with unity amplitude is 0.707.
Answer:
hello your question is incomplete attached below is the complete question
answer: Irms = 0.707*2[tex]\pi FcVo\\[/tex]
Explanation:
To derive the expression for the root mean square ( RMS ) current through the capacitor as a function of the applied voltage amplitude
RMS value of a sine wave with unity amplitude = 0.707
when the dc component is removed the i.e. the RMS signal = standard deviation ( signal )
attached below is the derivation
Janice has just measured the density of an object. Which value is possible? (Density: D = )
Explanation:
Density is an intensive property of matter.
It is the mass per unit volume of a substance and it is expressed mathematically below:
Density = [tex]\frac{mass}{volume}[/tex]
Mass is the amount of matter present within a substance
Volume is the space a substance occupies
So, density is directly proportional to the mass of a body and inversely related to the volume it occupies.
The packing of a substance is very important for determining the density values .
Which of the following is NOT a step used to perform a scientific inquiry
Answer:
b. Designing an uncontrolled experiment.
Explanation:
They always have it controlled.
Answer:
B. Designing an uncontrolled experiment.
Explanation:
Correct Answer!!!!!!
When testing a home for radon, where is the most likely place for the highest detected level? A) the basement, due to ground seepage B) the first floor, due to doors to the outside allowing radon to enter C) the second floor, due to the chimney effect D) all areas will have equal levels of radon E) radon cannot be tested because it is odorless, colorless, and tasteless
Answer:
A
Explanation:
ive been buying loui i been shoppin
Answer: E) radon cannot be tested because it is odorless, colorless, and tasteless
Explanation:
edge2021
a block of mas \( m \) = 4.8 kg slides head on into a spring of spring constant \( k \) = 430 N/m. When the block stops, it has compressed the spring by 5.8 cm. The coefficient of kinetic friction between block and floor is 0.28. \( (g =9.8m/s^2) \)
Answer:
See explanation below
Explanation:
The question is incomplete. The missing part of this question is the following:
"While the block is in contact with the spring and being brought to rest, what are (a)the work done by the spring force and (b) the increase in thermal energy of the blockfloor system? (c) What is the blocks speed just as it reaches the spring?"
According to this we need to calculate three values: Work, Thermal Energy and Speed of the block when it reaches the spring.
Let's do this by parts.
a) Work done by the spring:
In this case, we need to apply the following expression:
W = -1/2 kx² (1)
We know that k = 430 N/m, and x is the distance of compressed spring which is 5.8 cm (or 0.058 m). Replacing that into the expression:
W = -1/2 * 430 * (0.058)²
W = -0.7233 Jb) Increase in thermal energy
In this case we need to use the following expression:
ΔEt = Fk * x (2)
And Fk is the force of the kinetic energy which is:
Fk = μk * N (3)
Where μk is the coeffient of kinetic friction
N is the normal force which is the same as the weight, so:
N = mg (4)
Let's calculate first the Normal force (4), then Fk (3) and finally the chance in the thermal energy (2):
N = 4.8 * 9.8 = 47.04 N
Fk = 0.28 * 47.04 = 13.1712 N
Finally the Thermal energy:
ΔEt = 13.1712 * 0.058
ΔEt = 0.7639 Jc) Block's speed reaching the spring
As the block is just reaching the speed, the initial Work is 0. And the following expression will help us to get the speed:
V = √2Ki/m (5)
And Ki, which is the initial kinetic energy can be calculated with:
Ki = ΔU + ΔEt (6)
And ΔU is the same value of work calculated in part (a) but instead of being negative, it will be positive here. So replacing the data first in (6) and then in (5), we can calculate the speed:
Ki = 0.7233 + 0.7639 = 1.4872 J
Finally the speed:
V = √(2 * 1.4872) / 4.8
V = 0.7872 m/sHope this helps
2. Which of the following items would be the WORST conductor of electricity?
A. A steel rod
B. A copper wire
C. An aluminum bat
D. A rubber band
Answer: a rubber band
Explanation: A rubber band has no conductivity and no electricity would be able to flow whereas steel and copper and aluminum would be able to allow electricity to flow due to how they are built
Charlotte is driving at 66.5 mi/h and receives a text message. She looks down at her phone and takes her eyes off the road for 3.47 s. How far has Charlotte traveled in feet during this time
Answer:
the distance traveled by Charlotte in feet is 338.44 ft
Explanation:
Given;
speed of Charlotte, u = 66.5 mi/h
time of motion, t = 3.47 s
The distance traveled by Charlotte in feet is calculated as;
[tex]Distance = Speed \ \times \ time \\\\D = ut\\\\D = (\frac{66.5 \ mi}{h} \times \frac{5280 \ ft}{1 \ mi} \times \frac{1 \ h}{3600 \ s} )(3.47 \ s)\\\\D = 338.44 \ ft[/tex]
Therefore, the distance traveled by Charlotte in feet is 338.44 ft
Need help can anyone help me with this collision problem
Answer:
4 m/s
Explanation:
From the question given above, the following data were obtained:
Mass of 1st cart (m₁) = 20 kg
Initial velocity of 1st cart (u₁) = +6 m/s
Mass of 2nd cart (m₂) = 30 kg
Finally velocity of both cart (v) = 0 m/s
Initial velocity of 2nd cart (u₂) =?
The initial velocity of the 2nd cart can be obtained as follow:
m₁u₁ – m₂u₂ = v(m₁ + m₂)
(20 × 6) – (30 × u₂) = 0 (20 + 30)
120 – 30u₂ = 0(50)
120 – 30u₂ = 0
Collect like terms
– 30u₂ = 0 – 120
– 30u₂ = – 120
Divide both side by –30
u₂ = –120 / –30
u₂ = 4 m/s
Thus, the 2nd (i.e the 30 kg) cart was initially moving with a velocity of 4 m/s.
Sandy is riding a bicycle with tires that have a diameter of 650 mm. A small twig, caught in the spokes, causes the tire to click once each revolution. Of Sandy hears 8 such clicks every 3 seconds then how fast is she cycling (to the nearest km/hr)
Answer:
Explanation:
Sandy hears 8 such clicks every 3 seconds and a small twig, caught in the spokes, causes the tire to click once each revolution that means the wheel of the cycle is rotating at 8 rotations every 3 seconds or 8/3 rotation per second . In each rotation , it moves distance equal to its circumference .
circumference = 2π r = 2 x 3.14 x .65 / 2 m
= 2.041 m
In 8/3 rotation , distance covered = 8/3 x 2.041 = 5.44 m
So speed of cycle is 5.44 m per second
5.44 x 60 x 60 m per hour
19584 m per hour
= 19.584 km per hour .
= 20 km per hour approx.
Complete the following statement: Momentum will be conserved in a two-body collision only if a both bodies come to rest. b the internal forces of the two body system cancel in action-reaction pairs. c the kinetic energy of the system is conserved. d the net external force acting on the two-body system is zero. e the collision is perfectly elastic.
Answer:
d the net external force acting on the two-body system is zero
Explanation:
The net external force acting on the two-body system is zero .
During a collision , two internal forces appear on two bodies in opposite directions separately . As they act on each object separately , they do not cancel each other . But the net force on two body system is zero . Total momentum is always conserved during collision because no external force is involved . Collision is not always elastic .
What three factors affect the viscosity of magma
The factors that affect the viscosity of magma include temperature, crystal and rock fragments (composition), and the different dissolved gases.
What is magma?It is a mixture of solid, volatile and liquid materials.
Characteristics of the viscosity of magmaIt is a mixture of chemical components that form high-temperature silicates.It includes substance in solid, liquid and gaseous state due to the temperature of the magma which is above the melting points of certain components.Volcanic eruptions often occur when the vapor pressure of the gases becomes greater than the pressure exerted by the solid rocks that keep the magma confined.Therefore, we can conclude that the fluidity or viscosity of magma depends on its chemical composition and, in particular, the liquids and solids that the magma contains and the various gases dissolved in it.
Learn more about viscosity of magma here: https://brainly.com/question/20621986
The tub of a washer goes into its spin-dry cycle, starting from rest and reaching an angular speed of 4.0 rev/s in 9.0 s. At this point, the person doing the laundry opens the lid, and a safety switch turns off the washer. The tub slows to rest in 15.0 s. Through how many revolutions does the tub turn during this 24 s interval
Answer:
48 rev
Explanation:
a) we can calculate the distance covered by the tube using the formula:
θ = (ω + ωo)t/2
where ω is the final angular speed, θ is the distance covered, t is the time taken, ωo is the initial angular speed.
Firstly, we calculate the distance covered from 0 to 9 s then from 9s to 24 s.
within 9s, the tub runs from rest (0) to 4 rev/s, hence:
t = 9s, wo = 0, w = 4 rev/s = (4 * 2π) rad/s = 8π rad/s. Hence:
θ = (ω + ωo)t/2 = (0 + 8π)9 / 2 = 36π rad
θ = 36π rad = (36π)/2π rev = 18 rev
Also, within 15 s, the tub runs from 4 rev/s to rest, hence:
t = 15 s, wo = 4 rev/s = 8π rad/s, w = 0 rad/s. Hence:
θ = (ω + ωo)t/2 = (8π + 0)15 / 2 = 60π rad
θ = 60π rad = (60π)/2π rev = 30 rev
Therefore the total revolutions by the tube during 24 s interval = 30 rev + 18 rev = 48 rev
Using equations, determine the temperature, pressure and density of the air for a aircraft flying at 19.5 km. Is this aircraft subsonic or supersonic
Answer:
a) - 72.5°c
b) pressure = 3625.13 Pa
c) density = 0.063 kg/m^3
d) it is a subsonic aircraft
Explanation:
a) Determine Temperature
Temperature at 19.5 km ( 19500 m )
T = -131 + ( 0.003 * altitude in meters )
= -131 + ( 0.003 * 19500 ) = - 72.5°c
b) Determine pressure and density at 19.5 km altitude
Given :
Po (atmospheric pressure at sea level ) = 101kpa
R ( gas constant of air ) = 0.287 KJ/Kgk
T = -72.5°c ≈ 200.5 k
pressure = 3625.13 Pa
hence density = 0.063 kg/m^3
attached below is the remaining part of the solution
C) determine if the aircraft is subsonic or super sonic
Velocity ( v ) = [tex]\sqrt{CRT}[/tex] = [tex]\sqrt{1.4*287*200.5 }[/tex] = 283.8 m/s
hence it is a subsonic aircraft
Unpolarized light of intensity 30 W/cm2 is incident on a linear polarizer set at the polarizing angle θ1 = 22 ∘. The emerging light then passes through a second polarizer that is set at the polarizing angle θ2 = 162 ∘. Note that both polarizing angles are measured from the vertical. What is the intensity of the light that emerges from the second polarizer?
Answer:
I₂ = 8.80 W/cm²
Explanation:
To solve this exercise we need to apply the Malus's law.
First, when the light gors through the first polarizer which is linear, intensity is always cut in half, therefore:
I₁ = I / 2 (1).
Applying this, we have:
I₁ = 30 / 2 = 15 W/cm²
Now, we can calculate the intensity of the light, after it passes through the second polarizer. The Law of Malus states that light intensity will be:
I₂ = I cos²Ф (2)
Where Ф, is the difference between the angle of the first polarizer and the second. In this way we have:
Ф = α - β
Ф = 162 - 22 = 140°
Now, applying Malus's law we have:
I₂ = 15 cos²140°
I₂ = 8.80 W/cm²Hope this helps
* Psychology
Match the types of psychoactive drugs to their functions,
depressants
stimulants
amphetamines
hallucinogens
to excite neural activity and temporarily
elevate awareness
to increase dopamine activity and produce
schizophrenic-like paranoid symptoms
>
to inhibit the function of the central nervous
system and neural activity
to distort perceptions and effects on thinking
Answer:
See explanation below
Explanation:
Psychoactive drugs are drugs that affect the central nervous system. They alter cognitive function by changing mood and consciousness.
Examples;
Depressants: Inhibit the function of the central nervous system and neural activity.
Stimulants: Excite neural activity and temporarily elevate awareness.
Amphetamines: Increase dopamine activity and produce schizophrenic-like symptoms.
Hallucinogens: Distort perceptions and effects on thinking.
A drug is any substance that alters how the body functions.
What is a drug?A drug is any substance that alters how the body functions. There are different types of drugs that affect different parts of the body.
We shall now explain the following classifications of drugs;
depressants - to inhibit the function of the central nervousstimulants - elevate awarenesshallucinogens - to distort perceptions and effects on thinkingamphetamines - schizophrenic-like paranoid symptomsLearn more about drugs: https://brainly.com/question/6022349
the visible light spectrum ranges between what rays
An unstrained horizontal spring has a length of 0.29 m and a spring constant of 180 N/m. Two small charged objects are attached to this spring, one at each end. The charges on the objects have equal magnitudes. Because of these charges, the spring stretches by 0.021 m relative to its unstrained length. Determine (a) the possible algebraic signs and (b) the magnitude of the charges.
Answer:
A) they both have the same algebraic sign
B)6.377×10^-6 C
Explanation:
From columb's law, the force acting on both charges can be expressed as
F=( kq1*q2)/r^2
Where F= electrostatic force
r= distance between the charges
q1 and q2= charges
The force acting on a spring can be expressed as
F= kx..................eqn(2)
Where
K= spring constant = 180 N/m.
x= stretch of the string= 0.021m
Substitute the values into eqn (2)
F= (180×0.021)
F= 3.78N
If we compare with spring force,
Hence, F( electrostatic) = 3.78N
From
F=( kq1*q2)/r^2 ..............eqn(1)
Where
r= (0.29 m + 0.021m)= 0.311m
K= the electrostatic constant= 8.99×10^9 kg⋅m3⋅s−2⋅C−2.
If we substitute the values we have
Since the charges are the same, then
kq1 and q2 equals "q"
3.78= (8.99×10^9 ×q^2)/(0.311)^2
Making q^2 subject of the formula
3.78× (0.311)^2 = 8.99×10^9 × q^2
q^2= [(0.311)^2 × 3.78]/8.99×10^9
q^2= 40.668×10^-12
q=√40.668×10^-12
q= 6.377×10^-6 C
(a) the possible algebraic signs
They have the same algebraic sign
(b) the magnitude of the charges.
6.377×10^-6 C
The moon has a gravitational field strength (acceleration due to gravity) that is about 1/6 that of
Earth's. What is the gravitational field strength (acceleration due to gravity) on the moon?
Answer:
The gravitational field strength (acceleration due to gravity) on the moon is 1.63 m/s²
Explanation:
From the question, the moon has a gravitational field strength (acceleration due to gravity) that is about 1/6 that of Earth's.
To determine the gravitational field strength (acceleration due to gravity) on the moon, we will multiply the Earth's gravitational field strength (acceleration due to gravity) by 1/6.
Earth's gravitational field strength = 9.8 m/s²
∴ Moon's gravitational field strength = 1/6 × 9.8 m/s²
Moon's gravitational field strength = 1.63 m/s²
Hence, the gravitational field strength (acceleration due to gravity) on the moon is 1.63 m/s².
A fish finder uses a sonar device that sends 20,000-Hz sound pulses downward from the bottom of the boat, and then detects echoes. If the maximum depth for which it is designed to work is 85 m, what is the minimum time between pulses (in fresh water)?
Answer:
0.3106 seconds
Explanation:
Frequency= 20,000-Hz
The speed of echoes sounds can be calculated using the expression below;
Y= ( 2x/t) ...........................eqn(1)
t= overall time taken
x = maximum depth = 230m
Y= speed of echoes sounds
Speed of sound in water= 1,481 m/s which is a constant with little variation.
If we substitute the given values into eqn(1) we have
1481 = (2× 230)/ t
1481 × t= 460
t=460/1481
t=0.3106 seconds
Hence, the minimum time between pulses (in fresh water) is 0.3106 seconds
Consider a Carnot cycle executed in a closed system with 0.6 kg of air. The temperature limits of the cycle are 300 and 1100 K, and the minimum and maximum pressures that occur during the cycle are 20 and 3000 kPa. Assuming constant specific heats, determine the net work output per cycle.
Answer:
63.8 kJ
Explanation:
The net work output per cycle is the difference in heat input and heat output. The heat input and heat output are expressed as a function of volume ratios, while volume is expressed as a function of pressure and pressure as a function of temperature.
R = 287 J/kg.K, k = 1.4
Hence the net work input (W) is given as:
[tex]W=Q_{in}-Q_{out}\\\\W=mR[T_Hln\frac{V_2}{V_1} -T_Lln\frac{V_3}{V_4}]\\\\=mR[T_Hln\frac{P_1}{P_2} -T_Lln\frac{P_4}{P_3}]\\\\=mR[T_Hln(\frac{P_1}{P_3}(\frac{T_L}{T_H} )^\frac{k}{k-1}) -T_Lln(\frac{P_1}{P_3}(\frac{T_L}{T_H} )^\frac{k}{k-1})]\\\\=mR(T_H-T_L)ln(\frac{P_1}{P_3}(\frac{T_L}{T_H} )^\frac{k}{k-1})\\\\Substituting\ values:\\\\W=mR(T_H-T_L)ln(\frac{P_1}{P_3}(\frac{T_L}{T_H} )^\frac{k}{k-1})=0.6*287(1100-300)ln(\frac{3000*10^3}{2-*10^3}(\frac{300}{1100} )^\frac{1.4}{1.4-1})\\\\[/tex]
[tex]W=63.8\ kJ[/tex]
Tim has a weight of 500N, which his half of his father's
weight. He, his father and his uncle sit on a see saw. If
both Tim and his father sit on the right ended of the
see saw, 5m from the pivot, his uncle's weight is the
same his fathers. Where should Tim's uncle sit in order
to achieve a state of balance?
Answer:
3.75m on the left end
Explanation:
Given data
Tim's weight = 500N= 0.5kN
Tim's fathers weight= 500*2= 1000N= 1kN
Tim and the fathers weight = 500+1000= 1500N= 1.5kN
Tim's uncle weight= 1.5kN
Length of seesaw= 5m
let the distance Tim's uncle sits be x
We know that summation of clockwise moment equals the summation of anticlockwise moment
Taking moment about the center of the seesaw
1.5*2.5= 1*x
3.75= 1x
Divide boths sides by 1
x= 3.75/1
x= 3.75m
Hence Tim's uncle will sit 3.75m on the left end
A car traveling west at 15 m/s and speeds up to 20 m/s west in 5 seconds. Why is the acceleration of the car?
Answer:
1 m/s
Explanation:
5m/s change in velocity, divided by 5 seconds= 1 meter/second/second
change in velocity/change in time
Acceleration = (change in velocity) / (time for the change)
that's = (change in speed and its direction) / (time for the change)
Change in velocity = (ending velocity) - (starting velocity)
Change in velocity = (20 m/s west) - (15 m/s west)
Change in velocity = 5 m/s west
Acceleration = (5 m/s west) / (5 seconds)
Acceleration = 1 m/s west
Three people pull simultaneously on a stubborn donkey. Jack pulls eastward with a force of 83.5 N, Jill pulls with 93.3 N in the northeast direction, and Jane pulls to the southeast with 121 N. (Since the donkey is involved with such uncoordinated people, who can blame it for being stubborn
Answer:
235.8 N
Explanation:
Given that
Jack
83.5 east
Jill
93.3√2/2 east
93.3√2/2 north
Jane
121√2/2 east
121√2/2 south
From the above listed, we can calculate the total force component on x axis to be
Fx = 83.5 + 93.3√2/2 + 121√2/2
Fx = 83.5 + 65.97 + 85.56
Fx = 235 N (east)
Again, we calculate the total force component on y axis to be
Fy = 93.3√2/2 - 121√2/2
Fy = 65.97 - 85.56
Fy = -19.59 N (south)
Finding the resultant, we have
F = √(Fx²+Fy²)
F = √(235² + (-19.59)²)
F = √55225 + 383.7681
F = √55608.7681
F = 235.8 N
A disk is rotating with an angular velocity function given by ω=Kt+L. What is the angular acceleration of the disk at t=T ?
Answer:
Angular acceleration of the disk ∝ = K
Explanation:
Given that;
Angular velocity function given by ω = Kt + L
Angular acceleration of the disk at t=T is = ?
Now,
Angular velocity;
ω = Kt + L
Angular acceleration is;
∝ = dω / dt
= [tex]\frac{d}{dt}[/tex] ( Kt + L )
At t = T
∝ = K
Because ∝ is not dependent on t
Therefore
Angular acceleration of the disk ∝ = K
Followed by the previous question: presume that the electron performs a uniform circular motion around the hydrogen nucleus. What is the magnitude of the centripetal acceleration in m/sec2? (radius of the circle LaTeX: 5\times 10^{-11}5 × 10 − 11m; period of the motion LaTeX: 1.5 \times 10^{-16}1.5 × 10 − 16sec) Group of answer choices
Answer:
[tex]A_c=87.73*10^{21}m/s[/tex]
Explanation:
From the question we are told that
[tex]r=5\times 10^{-11}[/tex]
[tex]T=1.5 \times 10^{-16}[/tex]
Generally the equation for velocity is mathematically given as
[tex]Velocity (v)=\frac{2 \pi r}{t}[/tex]
[tex]V=\frac{2 \pi (5*10^{-11})}{1.5*10^{-16}}[/tex]
[tex]V=\frac{2 \pi (5*10^{-11})}{1.5*10^{-16}}[/tex]
Generally the equation for Centripetal acceleration is mathematically given as
[tex]A_c=\frac{V^2}{r}[/tex]
[tex]A_c=(\frac{20.944*10^5)}{r5*10^{-11}}[/tex]
[tex]A_c=87.73*10^{21}m/s[/tex]
please help asap!!
Explain the movement of a roller coaster in terms of potential and kinetic energy? When are these energies thegreatest? Smallest? Are they ever the same?
Answer:
Potential energy: Greatest at the top of the hill
Kinetic energy: Greatest at the bottom of the hill
The two meet at some point on the way down!
Explanation:
Potential energy is energy that represents an object's potential for motion. Kinetic energy is that object's energy during motion. They're two sides of the same coin, and in fact, their sum gets a special name: mechanical energy. Potential energy builds up in reaction to working against certain forces - in the case of the roller coaster, that primary force is gravity. Gravity exerts a downward force on the roller coaster, and it takes work to pull it up the hill.
When it reaches the peak, the coasters potential energy is at its highest, and the moment it crests over the hill and begins its descent, that gravitational potential energy starts converting into kinetic energy: the coaster starts accelarating down the track, and the potential energy decreases at the same rate that the kinetic energy increases.
At the bottom of the hill, all of that potential energy has become kinetic energy, and the coaster zooms along the track, hopefully not giving too many riders nausea
what are 2 bandwagon effect that can happen on students
Answer:
Below
Explanation: 1.Katie likes to read and would rather do that than play sports. Her friends make fun of her and tell her that reading is for nerds. Katie stops reading so much and starts to play sports more.
2. Marcus wants to go to a small community college close to home, but most of the kids in his class are applying to larger colleges out of state. Marcus decides that he should also apply to those colleges.