Answer:
the time interval that an earth observer measures is 4 seconds
Explanation:
Given the data in the question;
speed of the spacecraft as it moves past the is 0.6 times the speed of light
we know that speed of light c = 3 × 10⁸ m/s
so speed of spacecraft v = 0.6 × c = 0.6c
time interval between ticks of the spacecraft clock Δt₀ = 3.2 seconds
Now, from time dilation;
t = Δt₀ / √( 1 - ( v² / c² ) )
t = Δt₀ / √( 1 - ( v/c )² )
we substitute
t = 3.2 / √( 1 - ( 0.6c / c )² )
t = 3.2 / √( 1 - ( 0.6 )² )
t = 3.2 / √( 1 - 0.36 )
t = 3.2 / √0.64
t = 3.2 / 0.8
t = 4 seconds
Therefore, the time interval that an earth observer measures is 4 seconds
A main-sequence star at a distance of 20 pc is barely visible through a certain telescope. The star subsequently ascends the giant branch, during which time its temperature drops by a factor of three and its radius increases a hundredfold. What is the new maximum distance at which the star would still be visible in the same telescope?
Answer:
Explanation:
The surface area of a star estimated by the energy emitted per sq meter yields the overall luminosity, which can be represented mathematically as:
[tex]L= 4 \pi R^2 \sigma T^4 --- (1)[/tex]
where;
L ∝ R²T⁴
and;
R = radius of the sphere
σ = Stefans constant
T = temperature
Also; The following showcase the relationship between flux density as well as illuminated surface area as:
[tex]F = \dfrac{L}{A}[/tex]
where
A = 4πd² and L ∝ R²T⁴
[tex]F = \dfrac{R^2T^4}{4 \pi d^2} \\ \\ F \alpha \dfrac{R^2T^4}{ d^2} --- (2)[/tex]
Given that:
distance d₁ = 20 pc
Then, using equation (2)
[tex]F_1 \ \alpha \ \dfrac{R^2_1T^4_1}{ d^2_1}[/tex]
However, we are also being told that there is a temp. drop by a factor of 3;
So, the final temp. [tex]T_2 = \dfrac{T_1}{3}[/tex]; and the final radius is [tex]R_2 = 100R_1[/tex] since there is increment by 100 folds.
Now;
[tex]F_2 \ \alpha \ \dfrac{R^2_2T^4_2}{ d^2_2}[/tex]
SInce;
[tex]F_1 = F_2[/tex]
It implies that:
[tex]\dfrac{R^2_1T^4_1}{ d^2_1 } = \dfrac{R^2_2T^4_2}{ d^2_2} \\ \\ d_2 = \sqrt{\dfrac{R_2^2T_2^4}{R_1^2T_1^4}}(d_1)[/tex]
Replacing all our values, we have:
[tex]d_2 = \sqrt{\dfrac{(100R_1)^2 \times (\dfrac{T_1}{3})^4}{R_1^2T_1^4}}(20 ) \\ \\ d_2 = \sqrt{\dfrac{(100)^2 }{3^4}}(20 ) \\ \\ d_2 = \sqrt{\dfrac{(100)^2 }{3^4}}(20 ) \\ \\ d_2 =222 \ pc[/tex]
HELP ME PLEASEEEEEEEEEEEEEE
Answer:
the vacoule in a plant is larger than that of an animal
A woman is driving her car due east at a velocity of 10 m/s. If the woman has a mass of 50 kg and her car has a mass of 1.000 kg, what is the magnitude of the momentum of the woman and her car?
Answer: 10,500 kg m/s
Explanation: (1,000 + 50)(10)
The velocity of a particle is given by v=25t2 -80t-200, where velocity is meter per second and time is seconds. Determine the velocity for the first six seconds when acceleration is zero.
Answer:
v = 220 m / s
Explanation:
This is a kinematics exercise, the expression for velocity is
v = 25 t² - 80 t - 200
asks the velocity for time t = 6 s.
let's calculate
v = 25 6² - 80 6 - 200
v = 220 m / s
The velocity for the first six seconds when acceleration is zero is -44 m/s.
What is velocity?
The velocity of an object is the rate of change displacement with time.
The velocity of the object for the first six seconds when the acceleration is zero is calculated as follows;
[tex]a = \frac{dv}{dt} \\\\a = 50t - 80\\\\0 = 50t - 80\\\\50t = 80\\\\t = 1.6 \ s[/tex]
Velocity when time = 1.6 s
[tex]v(1.6) = 25(1.6)^2 - 80(1.6) - 200\\\\v(1.6) = -264 \ m/s[/tex]
The velocity for the first six seconds when acceleration is zero.
[tex]v = v_{a =0} + v_6\\\\v = - 264 \ + 25(6)^2 - 80(6) - 200\\\\v = -44 \ m/s[/tex]
Learn more about velocity here: https://brainly.com/question/6504879
Air(ideal gas) at 292.15k is expended by a piston from 600cm^3 to 900cm^3 at a temperature of 550k at 900kpa pressure. find the pressure before expansion.
Answer:
The pressure before expansion is 717.1 kPa.
Explanation:
We need to use the Ideal Gas equation to find the initial pressure:
[tex] PV = nRT [/tex]
Where:
P: is the pressure
V: is the volume
n: is the number of moles
R: is the gas constant
T: is the temperature
Since the number of moles does not change after the expansion, we need the following number of moles:
[tex] n = \frac{P_{f}V_{f}}{RT_{f}} [/tex] (1)
Where "f" is for final
Before the expansion, the pressure is:
[tex] P_{i} = \frac{nRT_{i}}{V_{i}} [/tex] (2)
By entering equation (1) into (2) we have:
[tex] P_{i} = (\frac{P_{f}V_{f}}{RT_{f}})(\frac{RT_{i}}{V_{i}}) [/tex]
[tex]P_{i} = \frac{P_{f}V_{f}T_{i}}{T_{f}V_{i}} = \frac{900 kPa*900 cm^{3}*292.15 K}{550 K*600 cm^{3}} = 717.1 kPa[/tex]
Therefore, the pressure before expansion is 717.1 kPa.
I hope it helps you!
True or False - Water changing between states of matter is an example of a physical change.
true. true is the correct answer
Mom cuts the cheese by pressing the knife with a force of 50N. What is the pressure of the knife blade into the cheese if the blade is 12 cm long and 0.2 mm wide?
Answer:
Pressure=Force/Area
F=50N
A= L x W
Change the units to metres
W= 0.2x10-³m
L= 12 x 10-²m
A= 0.2x10-³ x 12 x10-²
A=2.4x10^-5m²
P= 50/2.4x10^-5
= 2.08x10^6Nm-¹ ~ 2.1x10^6Nm-¹
What happens during nuclear fission? A) Nucleus forms from two smaller nuclei. B) two nuclei give off positrons C) A nucleus gives off an alpha particle D) Two or more nuclei forms when a larger nucleus splits
Answer:
it is d, just did the quiz. all this came from the amazing com mentor who said a was wrong and it is d, thank you.
Explanation:
This splitting of the big atomic nucleus into smaller nuclei is known as nuclear fission, and further discussion is as follows:
Nuclear fission:The neutron collides with a uranium atom that splits during the fission of nuclear, producing a tremendous quantity of energy in the form of heat produced. If a uranium atom splits, additional neutrons are extricated.
It proceeds to smash more uranium, and the cycle continues forever.The neutrons are absorbed into a nucleus in such a nuclear reactor. It transforms into uranium-236, which is extremely unstable. Its nucleus is split into two enormous shards known as 'daughter nuclei'.Therefore, the final answer is "Option D".
Find out more about the nuclear fission here:
brainly.com/question/913303
Please help to Calculate the lower and upper bound for 3.2 + 4.6
Answer:
i think it is 7.10Explanation:
I dont have an explenation
Which element has 1 valence electron in its outer shell and will react with a
group 17 element in a 1:1 ratio?
A. Strontium
B. Silicon
C. Lithium
D. Sulfur
Answer: C. Lithium
Explanation: Quizzed
C. Lithium has 1 valence electron in its outer shell and so will react with a group 17 element in a 1:1 ratio.
The last number of group that an element belongs to on the periodic table tells the number of valence electrons that it will have.
Lithium is in group 1 of the periodic table which means that it has only a single electron in its valence shell.Group 17 elements have seven valence electrons and so need one more to achieve stability which is why they will react with Lithium (which has that one electron) in a 1:1 ratio.
Some of those elements include:
Fluorine ChlorineBromineIodineIn conclusion therefore, Lithium has 1 valence electron and will react with group 17 elements in a 1:1 ratio.
Find out more at https://brainly.com/question/20516188.
Hi!!! Please help me, 25 points!! :D
Which material refracts the light rays the least: air, water, or glass?
Answer:
air
Explanation:
water is a liquid and can be refracted.
glass is a solid which can also be refracted.
however,
air you can't see just see mainly.
air is the answer.
hope this helps :)
Hello guys sana ok lng kau
sssssssssssss
Explanation:
Answer:
hello how are you
have a great day
Place the balloon in a bell jar. If available also add some shaving cream and fresh marshmallows. Ask the instructor for help if you are unfamiliar with this apparatus. The motor of the vacuum pump will remove air from the bell jar when it is turned on. Make a prediction about what you think will happen to the balloon as air is removed from the bell jar.
Answer:
The balloon will collapse
Explanation:
When air is removed from the bell jar, the balloon will collapse if the internal pressure from the balloon does not balance the atmospheric pressure from the surroundings.
A plane is heading south with a velocity of 150 kilometers/hour. It experiences a tallwind with a velocity of 20 kilometers/hour. Find the resultant
velocity of the plane.
A.120 kilometers/hour to the south
B.148 kilometers/hour to the north
C.170 kilometers/hour to the south
D.130 kilometers/hour to the north
E.150 kilometers/hour to the south
Answer: 170km/hr to the South
Explanation:
The resultant velocity of the plane ilwill be gotten by adding the value of the velocities of the plane with the tallwind. It should be noted that the direction of the wind is.takwn into consideration.
Therefore, the resultant velocity of the plane will be:
= 20km/hr + 150km/hr
= 170km/hr to the South
Answer:
Resultant Velocity = 20 km/h + 150 km/h = 170 km/h
Explanation:
A spring is hung from the ceiling. When a block is attached to its end, it stretches 2.6 cm before reaching its new equilibrium length. The block is then pulled down slightly and released. What is the frequency of oscillation?
Answer:
f = 3.09 Hz
Explanation:
This is a simple harmonic motion exercise where the angular velocity is
w² = [tex]\frac{k}{m}[/tex]
to find the constant (k) of the spring, we use Hooke's law with the initial data
F = - kx
where the force is the weight of the body that is hanging
F = W = m g
we substitute
m g = - k x
k = [tex]- \frac{m g}{x}[/tex]
we calculate
k = [tex]- \frac{9.8 m}{- 2.6 \ 10^{-2}}[/tex]
k = 3.769 10² m
we substitute in the first equation
w² = [tex]\frac{ 3.769 \ 10^2 \ m }{m}[/tex]
w = 19.415 rad / s
angular velocity and frequency are related
w = 2πf
f = [tex]\frac{w}{2\pi }[/tex]
f = 19.415 / 2pi
f = 3.09 Hz
Science questions!! Please help!!
Post Assessment on Investigating the Immune System
please help!! Please choose the right answers!! Dont guess if you dont know the answers!!
Answer: i think it is for 16, Infectious diseases commonly spread through the direct transfer of bacteria. for 17 i think In biology, immunity is the capability of multicellular organisms to resist harmful microorganisms. i dont have a clue about the others but i hope this is right or atleast helps
Explanation:
When a narrow laser beam passes through a fine wire mesh before arriving at the wall, it forms a complicated pattern of bright spots on the wall. This pattern of spots would not occur if you sent a flashlight beam through the mesh because light from the flashlight is not a single electromagnetic wave. cannot be sent through a single opening of the mesh. is horizontally polarized, while laser light is vertically polarized. is vertically polarized, while laser light is horizontally polarized.
Answer:
this pattern to occur there must be coherence in the light beams.
you use a flashlight, the rays are incoherent so diffraction patterns cannot occur.
Explanation:
The point pattern that appears in the wall is the result of the interference and diffraction processes through each space of the mesh, for this pattern to occur there must be coherence in the light beams.
The coherence process is that all the rays have the same constant and phase, before the appearance of the lasers, the light is stopped by a small opening and this ray is the one that passes through the slits, with the appearance of the laser this it is consistent from its production process, so opening is not necessary, with this there is much greater intensity and the measurement process is simplified.
When you use a flashlight, the rays are incoherent so diffraction patterns cannot occur.
Polarization has no effect on diffraction patterns so it does not matter if it is vertical or horizontal.
Drag the tiles to the correct boxes. Not all tiles will be used.
Match the molecular shapes to the correct Lewis structures.
trigonal pyramidal
trigonal planar
bent
tetrahedral
linear
Answer
1) AlH3= trigonal planar
2) CH2F2= tetrahedral
3) PH3= trigonal pyramidal
4) O3= bent
Explanation:
I took the test
As wavelength decreases the frequency of a wave _______
Question (Fill-In-the Blank):
As wavelength decreases the frequency of a wave _______
Answer:
Increases
Explanation:
When waves travel from one medium to another the frequency never changes. As waves travel into the denser medium, they slow down and wavelength decreases. Part of the wave travels faster for longer causing the wave to turn. The wave is slower but the wavelength is shorter meaning frequency remains the same.
[tex] \boxed{ \boxed{ \huge\mathrm{Answer࿐}}}[/tex]
[tex] \mathrm{wavelength \: \: \dfrac{1}{ \propto} \: \: frequency }[/tex]
So, As wavelength decreases the frequency of a wave Increases.
_____________________________
[tex]\mathrm{ \#TeeNForeveR}[/tex]
The disk weights 40 lb and has a radius of gyration is 0.6 ft. A 15 lb/ft moment is applied and the spring has a spring constant of 10 lb/ft. The system was initially at rest and the disk is rolling without slipping. The spring is initially unstretched. Find the angular velocity of the wheel when disk moves to the right 0.5 ft.
Answer:
angular velocity = 2.6543 rad/s
Explanation:
To find the angular velocity of the wheel when the disk moves to the right 0.5 ft, we need to be aware that the spring will stretch twice the value of gyration with any slight change in the position or movement of gyration since the top of the wheel is holding the spring.
The work done here:
= ((distance moved by the wheel) X spring constant X (Final displacement^2 - Initial displacement^2)) + Mass (q2 – q1)
Where q2 = 0.5ft
q1 = 0.8 lb
Note that linear velocity = radius X angular velocity
= -0.5(10)(1^2 – 0) + 15(0.5/0.8) = 4.375 ft·lb
Then, the kinetic energy :
Since the spring is initially unstretched, the initial tension in the spring = 0
So the final tension = ((distance moved by the wheel) X (linear velocity)^2 X (angular velocity) ^2 + (distance moved by the wheel) X (linear velocity) X ( radius of gyration) ^2 X (angular velocity) ^2
= 0.5(40/32.2)(0.8w) ^2 + 0.5(40/32.2)(0.6)^2 X w2
final tension = 0.621 w2
So the angular velocity of the wheel when disk moves to the right 0.5 ft = The Initial workdone + Initial kinetic energy will be equal to the final workdone + the final Kinetic energy
0 + 4.375 ft·lb = 0.621 w2
angular velocity = 2.6543 rad/s
7
The periodic table displays
A.
only the important compounds that exist in the world.
OB.
all of the known compounds that exist in the world today.
C.
only the important elements that exist in the world.
D.
all of the known tements that exist in the world today.
the density of brick is 1,600 kg/m3. what is the mass of a brick with a volume of 0.0006 m3? WILL MARK BRAINLIEST
Answer:
.0000004
Explanation:
The mass of a brick with a volume of 0.0006 m³ and a density of 1600 kg/m³ is 0.96kg.
HOW TO CALCULATE MASS?The mass of a substance can be calculated by multiplying the density of the substance by its volume. That is;
Mass = density × volume
According to this question, the density of brick is 1,600 kg/m3 and it has a volume of 0.0006m³. The mass is calculated as follows:
Mass = 0.0006 × 1600
Mass = 0.96kg
Therefore, the mass of a brick with a volume of 0.0006m³ and a density of 1600 kg/m³ is 0.96kg.
Learn more about mass at: https://brainly.com/question/19694949
distance moved by the effort in lifting the 5000N load to the height of 15m
Answer:
Hello There!!
Explanation:
Work done= force × distance moved
Work done=5000N×15m
Work done=75,000J
hope this helps,have a great day!!
~Pinky~
If you lived on Saturn, which planets would exhibit retrograde motion like that observed for Mars from Earth? (Select all that apply.)
Mercury
Venus
Earth
Mars
Jupiter
Uranus
Neptune
Answer:
earth , mercury , and neptune
Explanation:
pls mark brainless
a boy takes 20 minutes to cover 3.2 km on a bicycle find the speed in km/hr
Answer:
9.6 km/h
Explanation:
20 minutes=1/3 minute.
The speed of the bicycle: 3.2:1/3=9.6 km/h.
Answer: 9.6 km/h
a man counts 6 waves on a pond in 10 seconds. the distance between them is 40 cm. what is their speed?
Answer:
so a man counts 6 waves on a pound in 10 second
Explanation:
6×10 = 60
60/40
so the answer is3
what's the point of friendship?
Answer:
Friendships can have a major impact on your health and well-being, but it's not always easy to build or maintain friendships. Understand the importance of friendships in your life and what you can do to develop and nurture friendships
Which of the following is a terrestrial habitat?
A) Pond B) Garden C) Lake D) River
Answer:
garden
Explanation: All the other habitats are aquatic
Two concentric, circular wire loops of radii r1 and r2 (r1 < r2) are located in the x-y plane; each carries a current I in a clockwise direction. (a) Find the net dipole moment of this system. (b) Repeat for the reversed current in the inner loop
Answer:
a. πi(r₁² + r₂²)
b. πi(r₂²- r₁²)
Explanation:
(a) Find the net dipole moment of this system.
The magnetic dipole moment, μ = iA where i = current and A = For area
For the circular loop with radius r₁, and current i₁ in a clockwise direction, i₁ = + i positive
μ₁ = i₁A₁
= +i(πr₁²)
= πir₁²
For the circular loop with radius r₂, and current i₂ in a clockwise direction, i₂ = +i
μ₂ = i₂A₂
= +i(πr₂²)
= πir₂²
The net dipole moment, μ = μ₁ + μ₂
μ = μ₁ + μ₂
= πir₁² + πir₂²
= πi(r₁² + r₂²)
(b) Repeat for the reversed current in the inner loop
With the reversed current in the inner loop, the current is negative. So i₂ =-i
μ₁ = i₂A₁ = -i(πr₁²) = -πir₁²
So,
μ = μ₁ + μ₂
= -πir₁² + πir₂²
= πi(-r₁² + r₂²)
= πi(r₂²- r₁²)
Plz help w answer 1:/ confused ash
Answer:
I would say d I had the same question yesterday and I got it correct so hope that helps