Answer:
The Doppler Effect is given by the following relation;
[tex]f' = \left (\dfrac{v + v_0}{v - v_s} \right) \times f[/tex]
Where;
f' = The frequency the observer hears
f = Actual frequency of the wave
v = The velocity of the sound wave
[tex]v_o[/tex] = The velocity of the observer
[tex]v_s[/tex] = The velocity of the source
Where the observer is stationary, we have;
(i) When the source is moving in the direction of the observer
[tex]f' = \left (\dfrac{v }{v - v_s} \right) \times f[/tex]
(ii) When the source is receding from the observer, we have;
[tex]f' = \left (\dfrac{v }{v + v_s} \right) \times f[/tex]
Therefore;
(a) A person left behind on the platform
For a person left behind on the platform, we have that the radio source is receding, therefore, we have;
[tex]f' = \left (\dfrac{v }{v + v_s} \right) \times f[/tex]
(1) Given that (v + [tex]v_s[/tex]) > v, therefore, v < (v + [tex]v_s[/tex]), f' < f, the frequency heard by the person left on the platform, f', is smaller (lower) than the frequency produced by the radio
(2) The frequency is not constant as the speed of the source is increasing while it under the acceleration due to gravity
(3) During the fall, the speed of the source continuously increases under the effect of gravitational attraction and therefore the frequency heard by the person on the platform becomes progressively smaller
(b) A person down below floating on a rubber raft
For the the person down below on the rubber raft, the radio source is advancing
Therefore, the radio source is moving towards the person at rest down on the rubber raft, therefore, we have;
[tex]f' = \left (\dfrac{v }{v - v_s} \right) \times f[/tex]
(1) Given that (v - [tex]v_s[/tex]) < v, therefore, f' > f, the frequency heard by the person down below floating on the rubber raft, f', is greater (higher) than the frequency produced by the radio
(2) The frequency is not constant as the speed of the source is increasing while it under the acceleration due to gravity
(3) During the fall, the speed of the source continuously increases under the effect of gravitational attraction and therefore the frequency heard by the person on the platform becomes progressively greater (higher)
Explanation:
11. A sensitive thermometer is one which
A. Is sensitive to heat
B. has large bore
C. can record big changes in temperature
D. can record small changes in temperature
Answer:
A. ls sensitive to heat
this is correct answer
I hope it's helpful for you.......
I NEED THIS RIGHT NOW, PLEASE HELP!!!
Decribe what must happen inside of an aluminum can in order for it to be attracted to a positively-charged and to a negatively-charged object
Answer:
The PROTONS in the can attract to the negatively charged object, so then the can becomes polarized and the ELECTRONS in the can attract the positively charged object.
Explanation:
The PROTONS inside the can entice to the negatively charged object, so then the can will become polarized and the ELECTRONS in the can appeal to the undoubtedly charged item.
How are proton and electron associated?The number of protons within the nucleus of the atom is identical to the atomic range. The variety of electrons in an impartial atom is identical to the number of protons. The mass range of the atom (M) is equal to the sum of the wide variety of protons and neutrons inside the nucleus.
Protons definitely charged subatomic particles that live in the nucleus. Neutrons: Neutrally charged subatomic particles that are living in the nucleus. Electrons: Negatively charged subatomic debris found inside the electron shells surrounding the nucleus.
An electron is a negatively charged factor of an atom while the proton is an undoubtedly charged frame. The electrons are present out of doors the nucleus inside the orbiting shells. But the protons alongside neutrons shape the nucleus of the atom and are gifted in the middle of the atomic nuclei.
Learn more about electron and proton here: https://brainly.com/question/4894505
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Three resistors of resistances, R1=10Ω, R2=5Ω, R3=20Ω are connected in a circuit in such way that same amount of current flows through them. Draw a circuit diagram showing the correct connections of the three resistors, a cell of 2.5V, an ammeter and a voltmeter across R3. Calculate the potential difference across R3.
Answer
Explanation:
As the three resistors are connected in series, the expression to be used for the
calculation of RT equivalent resistance
is:
RT = R1 + R2 + R3
We replace the data of the statement in the previous expression and it remains:
5 10 15 RT + R1 + R2 + R3 + +
We perform the mathematical operations that lead us to the result we are looking for:
RT - 30Ω
Help pweaseeee ill give u a brainlest
Answer:
Mass of the larger object
8. An electric force F exists between two objects, both having thecharge, q. If the charge on one object is doubled to 2q, the force
between the objects becomes
A. 1/4 F
B. 1/2 F
C. 2F
D. 4F
Dani says, "This classroom is 11 meters long. A meter is longer than a yard, so if I measure the length of this classroom in yards, I will get less than 11 yards."
Do you agree with Dani ?
Answer:
im not sure i just need points....
Explanation:
to lift
With a pulley system, you use more rope (distance), but need less (blank) to lift
the load
Ok so it is working ok!
Which of the following shows the relationship between work and energy?
O A. Work = total energy
B. Work = gravitational potential energy
C. Work = change in kinetic energy
D. Work = change in nonconservative forces
What is the frequency of a wave with a period of 8s?
A family is driving from Vancouver to Calgary, a distance of 907.3 km. During the first 300 km, they average 92 km/h. They stop for lunch for 38 min. They arrive in Calgary 8 h and 21 min after their lunch break.. What was their average speed (in km/h) for the entire journey, including the break?
Answer:
89 i would say
Explanation:
Electrical potential is measured in units called what
Answer:
Electrical potential is measured in units called volts.
Describe the forces that are acting on a person who is standing still on a sidewalk, and identify whether the forces are balanced or unbalanced. Describe how the forces would change if the person started walking.
Answer:
a. i His weight and the normal force on him due to the ground
ii The weight and the normal force are balance
b. There are four forces acting on him while he is walking. These are the backward push due to his leg on the ground and the frictional force between his feet in the horizontal direction and, his weight and normal force on his feet in the vertical direction.
Explanation:
a. i Describe the forces that are acting on a person who is standing still on a sidewalk
His weight and the normal force on him due to the ground act on him while the person is standing on the sidewalk
ii. identify whether the forces are balanced or unbalanced.
The weight and the normal force are balance because, the person does not move in the vertical or horizontal direction.
b. Describe how the forces would change if the person started walking.
When the person starts walking, the backward push due to his leg on the ground and the frictional force between his feet and the ground now acts on him in the horizontal direction. The frictional force acts in the forward direction and tends to move him forward. His weight and normal force on his feet still act vertically and are both balanced since he does not move in the vertical direction.
So, there are four forces acting on him while he is walking. These are the backward push due to his leg on the ground and the frictional force between his feet in the horizontal direction and, his weight and normal force on his feet in the vertical direction.
1.) Cameron loads a wheelbarrow full of dirt. She then holds up both handles and begins to push it across her yard. The push Cameron uses to move the wheelbarrow is an example of
trajectory
motion
dynamics
force
2.) Jeremy is pushing his two children on a set of swings. He gives his daughter a push and she swings about three feet high. Jeremy gives his son the same push, but he only swings about two feet high. What could account for the difference in how high the kids got?
Jeremy's daughter has more mass, so it takes less force to get her into the air.
Jeremy's son has more mass, so it would take more force to reach the same height as his daughter.
Jeremy's son has less mass, so it would take more force to reach the same height as his daughter.
Jeremy's daughter has more mass, so she accelerates faster than his son.
Answer:
C (Force)
Explanation:
Cmon we should all know dis
Answer:
force and Jeremy's son has more mass
Explanation:
pushing requires force and the son moves less
A mechanic uses a screw driver to install a 1⁄4-20 UNC bolt into a mechanical brace. What is the mechanical advantage of the system? What is the resistance force if the effort force is 5 lb
Answer:
15.7 ; 78.5
Explanation:
Given that
The mechanic use a screw driver to install 1⁄4-20 UNC bolt
And, the effort force is 5lb
We need to find out the mechanical advantage
And, the resistance force
As we know that
The Mechanical advantage of a screw = Circumference ÷ pitch
where,
Circumference = pi × d
pi = 3.142, D = diameter
So,
Circumference = 3.142 × (1 ÷ 4)
= 0.785 in
Now
Pitch = 1 ÷ TPI
Here TPI (thread per inch) = 20
Pitch = 1 ÷ 20 = 0.05
So,
Mechanical advantage = 0.785 ÷ 0.05
= 15.7
Now Resistance force if effort force is 5lb
We know that
Mechanical advantage = Fr ÷ Fe
Here
Fe = effort force, Fr = resistance force
15.7 = Fr ÷ 5
Fr = 15.7 × 5
= 78.5 lbs
If the vehiche has a speed of 24.0 m/s at point a what is the force of the track on the vehicle at this point?
Question:
A roller-coaster vehicle has a mass of 500 kg when fully loaded with passengers. If the vehicle has a speed of 20.0 m/s at point A, what is the force exerted by the track on the vehicle at this point?
See attachment
Answer:
33700 Newton
Explanation:
Given
[tex]m = 500kg\\v = 24.0m/s\\r=10m[/tex]
First, we determine the forces acting on mass m.
They are: the force exerted by the track (Fn) and the weight of the vehicle (W)
So, the net force is:
[tex]F_{net} = F_n - W[/tex]
[tex]W=mg[/tex]
So:
[tex]F_{net} = F_n - mg[/tex]
Make Fn the subject
[tex]F_n = F_{net} + mg[/tex]
Fnet is calculated as:
[tex]F_{net} = F_c = \frac{mv^2}{r}[/tex] --- i.e. the centripetal force
So:
[tex]F_n = F_{net} + mg[/tex]
[tex]F_n = \frac{mv^2}{r} + mg[/tex]
[tex]F_n = \frac{500 * 24^2}{10} + 500 * 9.8[/tex]
[tex]F_n = 28800 + 4900[/tex]
[tex]F_n = 33700N[/tex]
Earth is protected from meteorites by... (please help T-T 10 points)
a. the Moon
b. the atmosphere
c. other planets
d. the Sun
If a fish is trying to capture insect hovering above the surface of water – how will it jump to catch it? Will it aim above or below what it sees? Explain.
Answer:
Above
Explanation:
yes
what forces are being used when walking a dog and how ?
2. Why is alcohol thermometer not suitable to measure high temperature?
Answer:
Alcohol thermometers are used rather than mercury thermometers in very cold regions because alcohol has a lower freezing point than mercury. Pure ethanol freezes at -115 degrees C, while mercury freezes at -38 degrees C.
Explanation:
It is less durable because alcohol evaporates faster than mercury. It cannot measure high temperature because of a low boiling point. It wets the walls of the thermometer, which can adversely impact the accuracy of readings
T/F The outer planets have solid surfaces that are very rocky and dense
Answer:
False
Explanation:
the inner planets have solid rocky dense surfaces
A hot-air balloon with a mass of 400 kilograms moves across the sky with 3,200 joules of kinetic energy. The velocity of the balloon is meters/second.
Answer:
4 m/s
Explanation:
KE =
Velocity of balloon will be 4 m/s.
!! Hope It Helps !!
A book is placed on a table and a bike moves on a road.
Which statement is correct?
Both the book and the bike have kinetic energy.
Both the book and the bike have potential energy.
The book has potential energy and the bike has kinetic energy.
The book has kinetic energy and the bike has potential energy.
The book has potential energy and the bike has kinetic.
kinetic energy is energy possessed when a object is in motion. The bike is moving. Therefore, it has kinetic energy. The book isn't moving. Hopefully that helped
Sara travels east 6 miles and then goes south 3 miles and then north 8 miles. What is her displacement? Round
your answer to two significant figures.
a
Ob
6.3 miles SW
7.8 miles SW
0 miles
5.7 miles SW
7.8 miles NE
6.3 miles NE
od
Оe
Of
5.7 miles NE
Oh
9.1 miles sw
9.1 miles NE
Answer:
Explanation:
so her displacement is the distance from the start... she's now at a point (6,5) away from the start.. so what's the length of the side of the right triangle made by one side of 6 and the other of 5
Yes.. use Pythagoras theorem to solve this
C = √([tex]6^{2}[/tex]+[tex]5^{2}[/tex])
C = √(36 + 25)
C = √61
C = 7.810 miles.. north east of where she started
C = 7.8 miles NE :P
The energy of a photon was found to be 3.38 x 10-19 J. Planck's constant is 6.63 x 10-34 J. S. Which color of light corresponds to this photon?
violet
green
yellow
red
Answer:
The correct option is (c).
Explanation:
Given that,
The energy of a photon is, [tex]E=3.38\times 10^{-19}\ J[/tex]
We need to tell the color of this light. We know that, the energy of a photon is given by :
[tex]E=\dfrac{hc}{\lambda}[/tex]
Where
c is the speed of light
[tex]\lambda=\dfrac{hc}{E}\\\\\lambda=\dfrac{6.63\times 10^{-34}\times 3\times 10^8}{3.38 \times 10^{-19}}\\\\\lambda=5.88\times 10^{-7}\ m\\\\\lambda=588\ nm[/tex]
The wavelength of yellow light is approx 580 nm. Hence, we can say that this photon corresponds to yellow light.
Answer:
B. Green
Explanation:
correct on EDGE2021
I need help plz!!! Please help...
Answer: 60
Explanation:
Identify the equation used to calculate the gravitational force (Fc) acting on a block on an inclined plane.
A) F=mg
B) F=mg sin
C) F=mg cos
D)F=mg tan
Answer:
the answer is b
Explanation:
The answer is b
Which of the following is an example of a chemical reaction? A. mixing sugar and water B. melting wax c. tearing up a piece of paper D.burning paper
Answer:burning paper
Explanation: it’s burned, you can’t put it back together ( you can’t undo a chemical reaction/ change )
Pls help!
sponge
sandworm
crab
sea star
flatworm
Which characteristic do these animals have in common
Answer:
they havve to stay in water to survive
Explanation:
So their are sea animals
A student is blowing against the mouthpiece of a 668mm flute (open at both ends) causing it to resonate. (The air inside and outside the flute is 24.5°C)
1) what is the speed of the sound in the flute?
2) what is the fundamental frequency of the note produced?
3) what is the wavelength of the sound wave?
Answer:
a) v = 345.5 m / s, b) f = 183.8 Hz, c) λ = 1,336 m
Explanation:
a) the speed of sound depends on the density of the medium and this depends on the temperature, therefore
v = [tex]v_o \ \sqrt{1+ \frac{T}{273} }[/tex]
where v₀ is the speed of sound at 0ºC v₀ = 331 m / s
v = 331 [tex]\sqrt{1 + \frac{24.5}{273} }[/tex]
v = 345.5 m / s
c) In the exercise they indicate that the flute is a tube with the two ends open, so that at each end there is a belly, the resonance is
λ / 2 = L
λ = 2L
λ = 2 0.668
λ = 1,336 m
b) let's apply the relationship between speed, wavelength and frequency
v = λ f
f = v /λ
f = 345.5 / 1.336
f = 183.8 Hz
