Answer:
A). Light moves faster than sound, so you hear thunder after you see lightning.
Explanation:
The lightning and thunder demonstrate that 'light travels faster than sound' which clearly portrays the relationship between the light and the soundwaves. When we see lightning in the sky before hearing the sound of thunder as the speed of light much higher than the speed of sound. Sound travels ~ 343 m/s or 1235 km/hr while light travels 300000 km/s. This difference in speed prevents us from considering lightning and thunder as the same thing. The 'sound is a pressure wave and therefore, takes time to travel and bounce back to our ears.' Thus, we happen to witness lightning first. Hence, option A is the correct answer.
____ charges are attract each other
Answer:
One positive and one negative
Please Help! When drawing free-body diagrams, does the label "centripetal force" get used? Explain why.
Explanation:
No. Centripetal force is a not a force itself, but rather a sum of forces. From Newton's second law:
∑F = ma
∑F = m v²/r
So centripetal force does not get used on a free body diagram.
Acceleration can be defined as the rate at which velocity
Answer here
Answer:
Acceleration can be defined as the rate at which velocity increases per second.
Assuming that the acceleration unit is
m/s^2
how much work must be done by frictional forces in slowing a 1000-kg car from 26.1 m/s to rest?
Answer:
Explanation:
Work done by the frictional force is 3.41x10^5 J
It is given that,
Mass of the car, m = 1000 kg
Initial velocity of car, u = 26.1 m/s
Finally, it comes to rest, v = 0
We have to find the work done by the frictional forces. Work done is equal to the change in kinetic energy as per work - energy theorem i.e.
W = −340605 J
or Hence, the correct option is (a).
Help.
Why do scientists believe that global warming is happening?
The law of conservation of energy states that
A. energy cannot be converted from one from to another
B. energy cannot be created or destroyed
C. energy resources must be used efficiently
D. energy is constantly being lost to friction
Answer:
B
Explanation:
Energy can not be destroyed only converted into another form of energy
Which graph shows the correct relationship between kinetic energy and speed?
Answer: D
Explanation:
Kinetic energy = 1/2mV^2
From the formula above, we can deduce that kinetic energy is proportional to the square of speed. That is,
K.E = V^2
Graphically, the relationship isn't linear but a positive exponential. Therefore, option D is the correct answer.
Answer:
The correct answer is D.
Explanation:
Hope this helps.
Boats use echo sounders. Pulses of sound waves are reflected by the sea bed and
detected by a sensitive microphone. The time between an echo sounder sending and
receiving a pulse is 0.005 s. The device calculates the depth of the sea, using the speed
of sound in sea water, which is 1500 m/s.
Use this information to calculate the depth of the sea. Show your working.
Answer: depth = 3.75 m
Explanation:
Taken the speed of the sound in sea to be V = 1500 m/s
The time between an echo sounder sending and receiving a pulse is 0.005 s. That is,
Total time T = 0.005
Formula for echo is:
V = 2X/T
Where X = distance covered
Substitute V and T into the formula
1500 = 2X/0.005
Cross multiply
7.5 = 2X
Make X the subject of formula
X = 7.5/2
X = 3.75 m
Therefore, the depth of the sea is 3.75 m
Which of the following is an example of a visual aid? A. a poster B. a pair of glasses C. a set of note cards D. a copy of a written report
Answer:
a pair of glasses
of course
The temp of equal masses of three different liquids A,BandC are 12°C,19°Cand 28°Crespectively . The temp when A and B are mixed is 16°C, and when Band C are mixed is 23°C.The temp when A and C are mixed is
Answer:
19.1°C
Explanation:
If A and B mix to give 16°C, A has risen by 4°C and B has fallen by 3°C;
If B and C mix to give 23°C, B has risen by 3°C and C has fallen by 5°C;
This means the energy transfered to cause a change of 3°C in B causes a change of 4°C in A and 5°C in C;
We can use this as a ratio (4:5);
The temperature difference between A and C is 16°C;
we add the two parts of the ratio (4+5) to get 9 and divide the temperature difference to get 16/9;
Next we multiply this by one of the parts of the ratio, so with 4, you get 64/9;
This number is the proportional temperature change in A upon mixing;
We then add this to the original temperature of A to get the resultant temperature of the mix like so:
64/9 + 12 = 19.1111...
You can do this alternatively using the other part of the ratio;
We would multiply the 16/9 by the 5 instead of the 4 to get 80/9;
This number is the proportional change in temperature in C upon mixing
Then subtract this from this from the original temperature of C and you should get the same answer:
28 - 80/9 = 19.1111...
Identify the clean sources of energy.
Answer:
biomass, geothermal, hydropower, solar, and wind.
hope this helped!
How does the value of the electrostatic force vary with the value (how many) of the charges?
Answer:
Electrostatic force is directly proportional to the amount of charge on each body under consideration.
Electrostatic force increases with increase in charge.
Electrostatic force decreases with decrease in charge.
Explanation:
Electrostatic force is the force between 2 charges which can be explained by the Coulomb's Law:
F= K (q₁)(q₂)/r²
Where
F= Electrostatic Force
K = Constant of Proportionality
(q₁) and (q₂) = Amount of charge on each body
r = Distance between two bodies carrying charge
If the value of (q₁) or (q₂) is increased considering the other factors remain constant, the value of F will also increase.
And vice versa.
What is the power of a lightbulb that transfers 60 joules of electrical energy in 15 seconds
Answer:
power=[tex]\frac{work done}{time taken}[/tex]
power=[tex]\frac{60joules}{15seconds}[/tex]
power=4J/s
Light ray A moves from air to water. Part of ray A is reflected at the air-water boundary. Which arrow in the image is the reflected ray?
E
OA. B
OB.
С
OC.
D
OD. E
Answer:
A. B
Explanation:
The image has been attached.
Reflected ray refers to the ray of light which is reflected back after striking a surface that is non-permeable.
The ray of light which is reflected before the ray touches the surface is said to the incident ray.
According to the given image, ray B is the reflected ray. Ray B is reflected in the air after the ray A strikes at the surface of the water.
B
Explanation:
Since mirrors reflect things, when you shine light at a mirror, it will bounce off of the mirror, or reflect, and shine the opposite direction of where the original light is pointed. The answer would be B because light doesn't go through the mirror, or run along it.
Think of when you through a basketball on the ground. If you bounce it at an angle, it won't just come back to you in the same angle. It will keep bouncing at the same angle you through it. This is pretty much what describes the relationship between ray A and ray B.
HOPE THIS HELPS!!!!!
A ___ force is not path-dependent and does not change the overall mechanical energy of an object.
Answer:
conservative
Explanation:
Nonconservative force is the force that depends on a path, however conservative does not depend on a path and it is not associated with the potential energy. When the work is done by an unconservative force, mechanical energy is added or removed. Friction is the best example for a non-conservative force. When these non-conservative forces are acting, the mechanical energy changes but these are not preserved.
hope this helped!
Answer: conservative
Explanation:
A conservative force is not path-dependent and does not change the overall mechanical energy of an object.
A conservative force is a force with the property that the total work done in moving a particle between two points is independent of the taken path, e.g. gravitational force or electric force.
A nonconservative force is one for which work depends on the path taken, e.g. frictional force.
what is the equivalet tempreture of 0 kelvin in celcius scale
HELP NEED IT IN 5 MIN
Answer:
-273.15 degree celcius
Explanation:
What scientific evidence supports the Big Bang theory?
Universe expansion
Redshift
Composition of the universe
All of the above
None of the above
Answer:A universe expansion
Explanation:
The earliest and most direct observational evidence of the validity of the theory are the expansion of the universe according to Hubble's law (as indicated by the redshifts of galaxies), discovery and measurement of the cosmic microwave background and the relative abundances of light elements produced by BBN.
On the moon, what would be the force of gravity acting on an object that has a mass of 7 kg?
Answer: 7 kg
Explanation:
Help needed.
(1) A small object carrying a charge of
[tex] - 5 \times {10}^{ - 9} \: c[/tex]
experiences a downward force of 10 Newton when placed at a certain point in an electric field
What is the electric intensity at that point.
2. Determine the electric potential due to a charge of
[tex]12 \times {10}^{ - 9} c[/tex]
at a point 6 cm from the charge.
3. A series arrangement of three capacitors of value at 8micro Farahds, 12 micro Farahds and 24 micro Farahds is connected in series with a 90—V battery
(a) Draw and open circuit diagram for this arrangement (b). Calculate the effective capacitance in the circuit
(c) On closed circuit calculate the charge on each capacitor when fully charged
(d) Determine the PD across the 8 micro Farahds capacitors.
Answer:
1. -2×10 ^-9
2. 1800v
3 (ii) 4micro Farhad
(iii) V = 3.60 ×10²
(Iv) 45v
Explanation:
I hope it helps
Calculate the wavelength of a nitrogen molecule moving at a speed of 523m/s.
Answer:
The de-Broglie wavelength of the nitrogen molecule is 0.0272 nm
Explanation:
The mass, m, of the nitrogen molecule, N₂ = 14.0076u = 28.0152 × 1.66 × 10⁻²⁷ kg
[tex]v_{rms}[/tex] of N₂ = 523 m/s
The de-Broglie wavelength is given as follows;
[tex]de-Broglie \, wavelength = \dfrac{h}{m\times v_{rms}}[/tex]
Where:
h = Planck's constant = 6.62607004 × 10⁻³⁴ m²·kg/s
Plugging in the values, we have;
[tex]de-Broglie \, wavelength = \dfrac{6.62607004 \times 10^{-34}}{28.0152 \times 1.66 \times 10^{-27}\times 523} = 2.72\times 10^{-11} \, m[/tex]
Hence, the de-Broglie wavelength of the nitrogen molecule = 0.0272 nm.
What was Neptune's distance from the Sun in 1989?
Answer:
4.5 Billion km :)
Explanation:
thats how it is
Answer:
About 3.8 billions miles from the Sun OR 4.82 kilometers
hope this helped!
1/25 force of gravity in distance
Answer: 25
Explanation:
The shape of an apple is considered what
the shape of an apple is considered a physical property
What force is required to give an object with mass 2000 kg an acceleration of
3.5 m/s2?
A. 571 N
B. 7000N
C. 10,500 N
D. 2535 N
Answer:
B
Explanation:
7,000N because the formula for finding force is F=MA (2000x3.5)N=7000N
Together, two students exert a force of 825 N in pushing a car a distance of 35 m.
How much work do the students do on the car?
Answer:
28875 Joule
Explanation:
W = F * d
W = 825*35 = 28875 J
The work done by the students in pushing a car at a distance of 35 meters would be 28875 Joules.
What is work done?The total amount of energy transferred when a force is applied to move an object through some distance
The work done is the multiplication of applied force with displacement.
Work Done = Force * Displacement
As given in the problem Together, two students exert a force of 825 Newtons in pushing a car at a distance of 35 meters, then we have to find out the work done by the students,
The force exerted by the students = 825 Newtons
The distance moved by car = 35 meters
work done by students = 825×25
=28875 Joules
Thus, the work done by the students would be 28875 Joules.
To learn more about work done, refer to the link;
brainly.com/question/13662169
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4. How does a molecule differ from an atom? (4 points)
Do you think a population besides the moon jellies’ consumer population (sea turtles) and resource population (zooplankton) could have caused the moon jelly population to increase in size?
Answer:
I didn't quite understand your question, but the moon jelly population will increase if there are either more zooplankton or less sea turtles.
More zooplankton means more food => higher population
Less sea turtles means that the moon jelly will be lest often consumed => higher population
Answer: Yes because the Orca will start to eat the moon jellies
Explanation: When the Sea Turtles start to get very low on population the Moon jellies are next in line also the sea turtles eat the moon jellies and since they eat the moon jellies the sea turtle has a bit of that taste in them so they will taste alike to the sea turtles.
Please help me answer this question! Will appreciate help very much. a) Draw a circuit to show 3 lights in series b) Draw a circuit to show 2 lights in parallel c) Draw a circuit that shows 2 lights in parallel which are both in series with a third light. d) What would happen to the 2 other lights if the third light in question c) fails
Answer:
C kind sir
Explanation:
Can someone give me a situation where energy is being transferred, transformed or both? Thank you!
These waves are often used as a means to transfer digital information such as a text message or website.
A)Infrared
B)Ultraviolet
C)Radio
D)Visible Light
Answer:The answer is C
Explanation:
The waves are often used as a means to transfer digital information such as a text message or website is radio waves. The correct option is C.
What is digital information?Digital information generally consists of data that is created or prepared for electronic systems and devices such as computers, screens, calculators, communication devices. These information are stored by cloud.
The wave used for the same purpose is radio waves which has the high frequency range.
Thus, the correct option is C.
Learn more about digital information.
https://brainly.com/question/4507942
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