Astronauts traveling toward Earth in a fastmovingspacecraft receive a radio signal from an
antenna on Earth. Compared to the frequency
and wavelength of the radio signal emitted from
the antenna, the radio signal received by the
astronauts has a
(1) lower frequency and a shorter wavelength
(2) lower frequency and a longer wavelength
(3) higher frequency and a shorter wavelength
(4) higher frequency and a longer wavelength
Answers
the antenna, the radio signal received by the astronauts has a (1) lower frequency and a shorter wavelength.
Answer:
3) Higher frequency and a shorter wavelength
Explanation:
The Doppler Effect occurs when the distance between the wave source and the observer is changing. As the astronauts move toward the source of the radio waves, the radio waves will reach them at a faster rate. The perceived frequency will be higher and the wavelength shorter.
Related Questions
A boy throws a football horizontally from a window that is 2.8 m above the ground. If he throws the ball with a speed of 12 m/s, how far from the window does the ball land? A. 11.2 m B. 0.23 m C. 9.1 m D. 4.3 m
What does it cost, if electricity is $0.0900 per kW ⋅ h ?
Uranium 235 can be split if it is hit by: a neutron a proton an electron a neutrino
If a compasses moved close to a magnet, the compass will always point?towards the earths north pole away from the earths south pole along the magnets field lines none of the above
Answers
Answer:
the density of ordinary (baryonic) matter in the universe
Explanation:
Deuterium detection is of interest because the amount of it may be related to the amount of dark matter in the universe, but precise measurements have been difficult to obtain. Due to the way in which deuterium was created in the Big Bang, an exact measurement of the amount of deuterium would allow scientists to set limits on the models of the great explosion.
Also, an exact measure of deuterium would be an indicator of the cosmic density of barions (ordinary matter), and that density of barions would indicate whether ordinary matter is dark and is found in regions such as black holes, gas clouds or brown dwarfs, or it is bright and can be found in the stars. This information will help scientists who try to understand the very beginning of our universe.
Answers
=Fgd
= 225N * 15M
= 3375 Nm
Final answer:
Alejandra does 3375 Joules of work against gravity when she climbs to the ledge at the top of the climbing wall.
Explanation:
In order to calculate the work done against gravity, we can use the formula: Work = Force x Distance. The force of gravity can be calculated using the equation: Force = mass x acceleration due to gravity. Given that Alejandra weighs 225 newtons and the distance she climbs is 15 meters, we can plug these values into the formula to find the work done:
Work= (225 N) x (15 m) = 3375 Joules
Therefore, Alejandra does 3375 Joules of work against gravity when she climbs to the ledge at the top of the climbing wall.
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with solution and formula<3
Answers
Final answer:
It takes approximately 47 seconds for the sound of thunder to reach you at 20°C temperature.
Explanation:
The time it takes for the sound of thunder to reach you can be determined using the formula:
Time = Distance / Speed
Sound travels at a speed of approximately 343 meters per second at 20°C. Therefore, to calculate the time it takes for the sound to reach you, divide the distance by the speed:
Time = 16,090 meters / 343 meters per second
Time = 46.97 seconds
So, it takes approximately 47 seconds for the sound of thunder to reach you at 20°C temperature.
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Answers
FALSE
Hope this helps! :)
How high up must the 7th floor be?
If you had thrown it at the same speed but at the 28th floor, how far from the base of the building would it land?
Answers
1) 31.1 m/s
The rock has been thrown straight out of the window: its motion on the horizontal direction is simply a uniform motion, with constant speed , because no forces act in the horizontal direction. The speed in a uniform motion is given by
where S is the distance traveled and t the time taken.
In this case, the distance by the rock before hitting the ground is and the time taken is
, so the initial speed is given by
2) 67.1 m
In this part of the problem we are only interested in the vertical motion of the rock. The vertical motion is a uniformly accelerated motion, with constant acceleration (acceleration of gravity) towards the ground. In a uniformly accelerated motion, the distance traveled by the object is given by
where t is the time. Substituting a=9.8 m/s^2 and t=3.7 s, we can find S, the vertical distance covered by the rock, which corresponds to the height of the 7th floor:
3) 230.1 m
The height of the 7th floor is 67.1 m. So we can assume that the height of each floor is
And so, the height of the 28th floor is
We can find the total time of the fall in this case by using the same formula of the previous part:
In this case, S=268.8 m, so we can re-arrange the formula to find t
And now we can consider the motion of the rock on the horizontal direction: we know that the rock travels at a constant speed of v=31.1 m/s, so the distance traveled is
And this is how far from the building the rock lands.
115/3.7 =31.08m/s^2
b. covalent bond
c. iconic bond
Answers
Answer:
In ionic compounds, electrons are transferred between atoms of different elements ... For example, two hydrogen atoms bond covalently to form an H2 molecule; each ... is released when one mole of H2 molecules forms from two moles of H atoms: ... atom in each pair is more electronegative: (a) N or P. (b) N or Ge. (c) S or F.
Explanation: