Important Formulas:
[tex]w=Fd[/tex]
work(measured in joules) = force(measured in newtons) * distance(measured in meters)
__________________________________________________________
Given:
[tex]m=42kg[/tex]
[tex]F=180N[/tex]
[tex]w=2500J[/tex]
[tex]d=?[/tex]
__________________________________________________________
Rearranging work formula to make distance the subject:
[tex]w=Fd[/tex]
[tex]\dfrac{w}{F} =\dfrac{Fd}{F}[/tex]
[tex]d=\dfrac{w}{F}[/tex]
__________________________________________________________
Finding distance:
[tex]d=\dfrac{w}{F}[/tex]
[tex]d=\dfrac{2500}{180}[/tex]
__________________________________________________________
[tex]\fbox{d = 13.89 meters}[/tex]
A solenoid is connected to a battery as shown in the figure, and a bar magnet is placed nearby. What is the direction of the magnetic force that this solenoid exerts on the bar magnet? (Hint: Think of the solenoid as a bar magnet, and identify what would be its north and south poles.)
According to the right-hand rule, the magnetic field of the solenoid will be directed towards the left direction.
What is Right-hand rule?Right Hand Thumb Rule is the rule which is used If a current carrying conductor is imagined to be held in the right hand direction such that the thumb always points along the direction of the current flow, then the direction of the wrapped fingers in the hand will give the direction of the magnetic field lines of the bar magnet.
By the application of the right-hand rule, the magnetic field of the solenoid will be directed towards the left hand direction.
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Two protons are held a distance d apart. The electrostatic force and the gravitational force that one proton exerts on the other are Fe and Fg, respectively. Which of the following correctly compares the magnitude and direction of these forces?
Fe > Fg, opposite direction
a. Fe > Fg, same direction
b. Fe < Fg opposite direction
c. Fe < Fg same direction
Answer:
Explanation:
charge on each proton = 1.6 x 10⁻¹⁹ C
mass of proton = 1.67 x 10⁻²⁷ kg
Electrostatic force of repulsion Fe = 9 x 10⁹ x ( 1.6 x 10⁻¹⁹ )² / d²
= 23.04 x 10⁻²⁹ / d²
Gravitational force of attraction = G Mm / d²
M = m = 1.67 x 10⁻²⁷ kg
Gravitational force of attraction Fg = 6.67 x 10⁻¹¹ x ( 1.67 x 10⁻²⁷ )² / d²
= 18.60 x 10⁻⁻⁶⁵ / d²
So Fg is far less than Fe and former is attractive , later is repulsive .
Fe > Fg, opposite direction , is the answer .
Two parallel plates are charged
with 4.98*10^-7 C of charge.
What must the area of the plates
be to create an electric field of
8720 N/C?
(Unit = m^2)
Answer:
6.45
Explanation:
Got it right on Acellus
Critical angle of glass is 42 .what does it mean?
Answer:
i think..its fraction that its have multiple fractions on it..if you minus the 397 000-355 it should be 381+ so i say if you get the 5 multiply it by 9!! so you will get it!
Explanation:
HOPE IT HELPS!!
what is the normal force on a 2000N refrigerator resting on the ground
The perpendicular force that a surface applies to an item is known as the normal force. FN = m ⋅ g
What is Normal force?The perpendicular force that a surface applies to an item is known as the normal force. For instance, if you place a book on a table, a gravitational force will cause it to fall. The table pulls on the book in order to counterbalance this force and keep it from dropping. The normal force, often known as the opposing force, is denoted by the symbols FN F N or NN. "N" stands for the normal force unit (Newton).
A common illustration of Newton's third rule of motion is the normal force.
When one object applies force to another, the other applies a force in the opposite direction and of equal magnitude to the first object (action equals reaction).
Therefore, the force applied by the item to the surface is equal to the normal force. The calculations change according to the surface's slope.
The formula is as follows for an object laying on a flat surface:
FN = m ⋅ g
where
The mass of an object is m.
Gravitational acceleration is denoted by g.
The normal force (FN F N ) for an item on a flat surface is equal to its gravitational force, according to Newton's third law ( WW).
The formula is as follows for an object laying on a flat surface:
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A solid circular rod that is 600 mm long and 20 mm in diameter is subjected to an axial force of P = 50 kN. The elongation of the rod is delta = 1.40 mm and its diameter becomes df = 19.9837 mm. Determine the modulus of elasticity (E) and the modulus of elasticity in shear (G). Assume the material does not yield.
Answer:
a) the modulus of elasticity (E) is 68.22 GPa
b) the modulus of elasticity in shear is 25.28 GPa
Explanation:
Given the data in the question;
First we determine the cross-sectional area A of the road;
A = π/4 × d²
given that; diameter d = 20 mm
we substitute
A = π/4 × ( 20 mm )²
A = π/4 × 400 mm
A = 314.159 mm²
Next, we find, the normal stress of the rod σ
σ = P / A
given that load p = 50 kN = 50,000 Newton
we substitute
σ = 50,000 N / 314.159 mm²
σ = 159.155 N/mm²
σ = 159.155 Mpa
Next, is the normal strain ε
ε = δ / L
given that; change in length δ = 1.40 mm and Length of rod L = 600 mm
we substitute
ε = 1.40 mm / 600 mm
ε = 0.002333
Now, we find the modulus of elasticity;
we know that;
σ = Eε
modulus of elasticity E = σ / ε
we substitute
E = 159.155 Mpa / 0.002333
E = 68219.031 MPa
E = ( 68219.031 / 1000 ) GPa
E = 68.22 GPa
Therefore, the modulus of elasticity (E) is 68.22 GPa
b)
we know that the Poisson's ratio v is;
v = -(ε[tex]_{lat[/tex] / ε )
v = - (((d[tex]_f[/tex] - d)/d) / ε )
where d[tex]_f[/tex] is the final diameter of the rod ( 19.9837 mm ) and ε[tex]_{lat[/tex] is the lateral strain
so we substitute
v = - ((( 19.9837 - 20 ) / 20 ) / 0.002333 )
v = - (( -0.0163 / 20 ) / 0.002333 )
v = - ( - 0.000815 / 0.002333 )
v = - ( - 0.3493 )
v = 0.3493
So, our shear modulus will be;
G = E / 2( 1 + v )
we substitute
G = 68.22 GPa / 2( 1 + 0.3493 )
G = 68.22 GPa / 2( 1.3493 )
G = 68.22 GPa / 2.6986
G = 25.28 GPa
Therefore, the modulus of elasticity in shear is 25.28 GPa
The magnitude of the charge on an electron compared to the magnitude of the charge on a proton (3 points)
a) is greater
b) is smaller
c) is the same
Option C is correct.
The magnitude of the charge on an electron compared to the magnitude of the charge on a proton is same.
We have a electron and a proton.
We have to estimate the fact whether the magnitude of the charge on an electron compared to the magnitude of the charge on a proton is -
a) is greater
or
b) is smaller
or
c) is the same
What is the Electric charge ?The sufficiency or deficiency of electrons is called electric charge.
According to the question -
The charge on a electron is - q(e) = - 1.6 x [tex]10^{-19}[/tex] Coulombs
The charge on a proton is - q(p) = + 1.6 x [tex]10^{-19}[/tex] Coulombs
But, according to the property of magnitude :
| + x| = + x
| - x| = - (- x) = + x
In the similar manner -
|q(e)| = |q(p)| = 1.6 x [tex]10^{-19}[/tex] coulombs
Hence, the magnitude of the charge on an electron compared to the magnitude of the charge on a proton is same.
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both of yall are right and wrong its b and d
Answer:
Yup
Explanation:
When a low-pressure gas of hydrogen atoms is placed in a tube and a large voltage is applied to the end of the tube, the alors will emit electromagnetic radiation and visible light can be observed. If this light passes through a diffraction grating, the resulting spectrum appears as a pattern of four isolated, sharp parallel lines, called spectral lines. Each spectral line corresponds lo one specific wavelength that is present in the light emitted by the source. Such a discrete spectrum is referred to as a line spectrum
By the early 19th century, it was found that discrete spectra were produced by every chemical element in its gaseous slale. Even though these spectra were found to share the common feature of appearing as a set of isolated lines, it was observed that each element produces its own unique pattern of lines. This indicated that the light emitted by each element contains a specific set of wavelengths that is characteristic of that element.
part A What is the wavelength of the line corresponding to n =4 in the Balmer series? Express your answer in nanometers to three significant figures.
Part B What is the wavelength of the line corresponding to t=5 in the Balmer series? Express your answer in nanometers to three significant figures.
Answer:
A) λ = 4.88 10² nm, B) λ = 4.08 10² nm
Explanation:
The spectrum of hydrogen is correctly explained by the Bohr model, where the energy of each level is
Eₙ = -13.606 /n² [eV]
the transition generally occurs from a given level to a lower state nf <no, so a transition is
ΔE = E_f -Eₙ = -13,606 ( [tex]\frac{1}{n_f^2} - \frac{1}{n_o^2}[/tex] )
to find the wavelength let's use the planck relation
ΔE = h f
the speed of light is
c = λ f
we substitute
ΔE = h c /λ
λ = [tex]\frac{h \ c}{ \Delta \lambda}[/tex]
let's apply this equation to our case
the Balmer series has as final state the level n_f = 2
A) initial state n₀ = 4, final state n_f = 2
ΔE = -13.606 ( [tex]\frac{1}{2^2} - \frac{1}{4^2}[/tex] )
ΔE = 2.55 eV
let's reduce to SI units
ΔE = 2.55 eV (1.6 10⁻¹⁹ J / 1 eV) = 4.08 10⁻¹⁹ J
we calculate
λ = 6.63 10⁻³⁴ 3 10⁸ / 4.08 10⁻¹⁹
λ = 4.875 10⁻⁻⁷ m
we reduce to nm
λ = 4.875 10⁻⁷ m (10⁹ nm / 1m)
λ = 487.5 nm
we reduce to three significant figures
λ = 4.88 10² nm
B) initial state n₀ = 5
ΔE = -13,606 ( [tex]\frac{1}{2^2} - \frac{1}{5^2}[/tex] )
ΔE = 2,857 eV
we repeat the process of the previous point
ΔE= 2,857 1.6 10⁺¹⁹ = 4.286 10⁻¹⁹J
we look for the wavelength
λ = 6.63 10⁻³⁴ 3 10⁸ / 4.88 10⁻¹⁹
λ = 4.0758 10⁻⁷ m
we reduce to nm
λ = 4.0758 10² nm
ignificant numbers
λ = 4.08 10² nm
At the gym, a man pulls a bar on a machine that works the muscles of the upper back. It takes him 0.5 seconds to raise 30 kilograms of weights a vertical distance of 0.5 meters. Which of these exerts the same power output? (Estimate g as 10 m/s2.)
A) lifting 25 kilograms a distance of 2.4 meters in 2.0 seconds
B) lifting 45 kilograms a distance of 2.4 meters in 3.0 seconds
C) leg pressing 45 kilograms a distance of 0.5 meters in 0.5 seconds
D) bench pressing 30 kilograms a distance of 0.5 meter in 1.5 seconds
Answer: Lifting 25 kilograms a distance of 2.4 meters in 2.0 seconds
Explanation:
Got it wrong and that’s the answer
Lifting 25 kilograms a distance of 2.4 meters in 2.0 seconds exerts the same power output. Hence, option (A) is correct.
What is power?The quantity of energy moved or converted per unit of time is known as power in physics. The watt, or one joule per second, is the unit of power in the International System of Units.
Power is also referred to as activity in ancient writings. A scalar quantity is power.
Power required for lifting 30 kilograms of weights a vertical distance of 0.5 meters in 0.5 second = (30×9.8×0.5)/0.5 watt = 294 watt.
Power required for lifting 25 kilograms a distance of 2.4 meters in 2.0 seconds= (25×9.8×2.4)/2.0watt = 294 watt.
Power required for lifting 45 kilograms a distance of 2.4 meters in 3.0 seconds = (45×9.8×2.4)/3.0watt = 352.8 watt.
Power required for lifting 45 kilograms a distance of 0.5 meters in 0.5seconds = (45×9.8×0.5)/0.5watt = 441 watt.
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HELPPP PLEASEEEEE, BRIANLEST WILL BE GIVEN ON CORRECT!
Answer:
a. 25000J or 25KJ
b.2500w
Explanation:
a. since we say work is force applied in the same line or straight line
W=F(newtons )*D(metres)
b. power is work over time
Answer:
25000 J work with 2500 W power
Explanation:
work done = force . displacement = 500 N . 50 m= 25000 J
Power= work done / time taken = 25000 J / 10 s = 2500 W
A physics instructor wants to project a spectrum of visible light colors from 400 nm to 700 nm as part of a classroom demonstration. She shines a beam of white light through a diffraction grating with 500 lines per mm, projecting a pattern on a screen 2.4 m behind the grating. How wide is the spectrum corresponding to m=1?
Answer:
औडंठः की दुनिया कार्टून दर्शन होली है और यह बियर का अच्छा विकल्प है। विकल्प है। यो कुरा मेरो आफ्ना लागि विचार र त्यहाँको बडेमाको बिल्डिङ भित्र म जिन्दगी एक यात्रा हो कहाँबाट शुरु भइ कहाँ पुगेर अन्त हुन्छ
Electromagnetic induction occurs when
a.
b.
a conductor is moved through a magnetic
a magnet is connected to an electrical circ
electrons are rubbed from one object onto
electrons flow from one chemical to anoth
C.
d.
your hd
Answer:
A
Explanation:
occurs when a magnetic feild and an elctric conductor move relative to one another
How much force is needed to accelerate a 100 kilogram car 5 meters per second?
The force needed to accelerate the mass of 100 kg is 500 N.
What is force?Force is the product of mass and acceleration. The S.I unit of force is Newton (N).
To calculate the amount of force needed to accelerate the mass of 100 kg, we use the formula below.
Formula:
F = ma.................. Equation 1Where:
F = Forcem = Mass a = AccelerationFrom the question,
Given:
m = 100 kga = 5 m/s²Substitute these values into equation 1
F = 100×5F = 500 NHence, the force is 500 N.
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Add the following and give the answer using significant figures 5000+621
Answer:
;) hope it's helpful
Explanation:
5000 + 621 = 5621
Facts about 5621
Sig Figs
4
5621
Decimals
0
Scientific Notation
5.621 × 103
E-Notation
5.621e+3
Words
five thousand six hundred twenty-one
______is the amount of matter in an object. It does not change regardless
of location
__________which one
Friction
Mass
Weight
Answer:
Mass
Explanation:
The weight of an object is dependent upon the mass and the value of acceleration due to gravity:
W = mg
Since the value of acceleration due to gravity (g) changes from planet to planet. Hence, the weight of an object also changes with location.
Friction depends upon the material of surfaces and the weight.
F = (coefficient of friction)W
Since weight changes with location. Therefore, the friction also changes with location.
The mass of an object is the quantity of matter contained in the body. It remains constant anywhere in the universe.
Hence, the correct option is:
Mass
PLEASE HELPPP ASAP, I'LL GIVE BRAINLEST
Answer:
a) Joules
b) W (symbol for work) (J is symbol for Joules)
c) seconds
d) watts
PLEASE HURRY I GIVE BRAINLIST and extra points !!!!!!
1 What happens to the energy from the light when the material changes?
2 What happens to the energy from the light when the material does not change?
Answer:
2 stays the same 1 it will go bad or go good depends on which material you use
Which of the following is NOT a scientific hypothesis?
A. Neon atoms emit red light.
B. There is an attractive force between the earth and moon.
C. Halle Berry is attractive.
D. Summer days are hottest
E. The sky is blue.
The following statement is not a scientific hypothesis:
C. Halle Berry is attractive.
A scientific hypothesis is a proposed explanation for an observation or pattern in nature that can be tested through further investigation and experimentation. It should be testable, falsifiable, and based on evidence.
Neon atoms emit red light. This is a scientific hypothesis that can be tested and confirmed by looking at the spectrum of light emitted by neon atoms.
B. There is an attractive force between the earth and moon. This is a scientific hypothesis that can be tested and confirmed by measuring the force of gravity between the earth and moon.
D. Summer days are the hottest of the year. This is a scientific hypothesis that can be tested and confirmed by collecting temperature data during the summer months.
E. The sky is blue. This is a scientific hypothesis that can be tested and confirmed by observing the sky under different atmospheric conditions.
The statement "Halle Berry is attractive" is a subjective opinion that cannot be tested or confirmed through scientific investigation, hence it is not a scientific hypothesis. Attractiveness, as a concept, can vary widely based on personal, cultural, and social factors.
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A brick is thrown upward from the top of a building at an angle of 10° to the horizontal and with an initial speed of 15 m/s. If the brick is in flight for 2.9 s, how tall is the building? any help would be greatly appreciated
The total height of the building from which the brick is thrown is 33.60 meters.
What is Speed?
Speed is the rate of change of position of an object in any direction with respect to time. Speed is measured as the ratio of distance to the time in which the distance was covered. The SI unit of speed is m/s (meter per second).
The time of flight of the object from the building is:
t = 2μ sinθ/ g
t = 2 × 15 × sin10/ 9.8
t = 30 × 0.175/ 9.8
t = 0.535 seconds
Total time to cover the distance = 2.9 seconds
Total time = 2.9 - 0.535
Total time = 2.365
μg = μ sinθ
h = 15 × sin10 × 2.365 + 1/2 × 9.8 × (2.365)²
h = 2.625 × 2.365 + 1/2 × 9.8 × (2.365)²
h = 6.20 + 4.9 × 5.59
h = 6.20 + 27.40
h = 33.60 meters
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Part E
Once you complete your outline, write a 500- to 750-word paper using word processing software. Add a works cited page at the end to give credit to your sources. Submit your completed paper along with this activity to your teacher for evaluation.
A Voyage to Proxima Centauri
Proxima Centauri is the second closest star to our solar system, which makes scientists curious to know more about it. What do we know about Proxima Centauri? How did we discover this information? Is it possible for humans to travel to this star? In this task, you will research and write a 500- to 750 word paper that answers these questions. Follow these steps to complete your research and writing. This guide about the research process can help.
Estimated time to complete: 3 hours
Part A
The goal of your paper is to describe the history of the discovery and research of Proxima Centauri. Another goal is to find the possibilities of traveling to this star. Some questions that your paper should answer are:
When was Proxima Centauri discovered?
How was Proxima Centauri discovered?
How have scientists researched Proxima Centauri?
What technologies have they used? What types of data do these technologies collect?
Have spacecraft ever reached this star?
What are the limitations of sending spacecraft to Proxima Centauri?
What accommodations would humans need to travel to Proxima Centauri?
Proxima Centauri otherwise known as Alpha Centauri C, is the closest star to our solar system, located about 4.24 light-years away. It was discovered in 1915 by Robert Innes, the director of the Union Observatory in South Africa. Innes identified Proxima Centauri as a possible member of the Alpha Centauri system after noticing that the star had a similar proper motion to Alpha Centauri A and B.
Proxima Centauri was first observed through telescopes, which allowed scientists to study the star's spectra and estimate its distance from Earth. In the following decades, scientists continued to study Proxima Centauri through telescopes, including the Hubble Space Telescope, which provided high-resolution images of the star.
In 2016, the European Southern Observatory announced the discovery of an exoplanet orbiting Proxima Centauri, called Proxima Centauri b. This discovery was made using the radial velocity method, which measures the star's small wobbles caused by the gravitational pull of an orbiting planet.
What are the major challenges facing the discovery of Proxima Centauri?Despite the advances in our understanding of Proxima Centauri, no spacecraft have ever reached this star. The distance between Proxima Centauri and Earth is so vast that it would take tens of thousands of years to reach the star using current propulsion technology.
One potential solution to this problem is the use of interstellar travel, which would allow humans to travel to Proxima Centauri within a human lifetime. There are several proposed methods for interstellar travel, including using a starship propelled by fusion engines or a massive light sail pushed by a beam of lasers. However, these technologies are still in the theoretical stage and have not yet been developed.
There are also many other challenges that must be overcome in order for humans to travel to Proxima Centauri. For example, humans would need to find a way to protect themselves from the high levels of radiation that they would be exposed to during the journey. They would also need to find a way to provide enough food, water, and other resources to sustain themselves for the duration of the trip.
Overall, while it is theoretically possible for humans to travel to Proxima Centauri, it would be a massive undertaking that would require significant technological advancements and the development of new solutions to many challenges.
Sources of Works Cited include:
"Proxima Centauri." Wikipedia, Wikimedia Foundation, 5 Jan. 2021,
"Proxima Centauri b." Wikipedia, Wikimedia Foundation, 20 Nov. 2020,
"Interstellar Travel." Wikipedia, Wikimedia Foundation, 4 Jan. 2021,
Therefore, the correct answer is as given above
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Can anyone help with this?
Answer:
Explanation:
Add a horizontal line. An object that is not moving has no change in distance with respect to time.
It takes one year for ______.
a.earth to circle the sun one time
b.earth to rotate on its axis one time
c. The sun to circle earth one time
d.the sun to rotate on its axis one time
Answer: A. Earth to circle the sun one time.
How does heat transfer?
PLEASE HELP MEEEEEEE:((((
Here's the solution,
A.)
we know,
[tex]power = \dfrac{work \: done}{time} [/tex]
so,
=》
[tex]600 = \dfrac{work \: done}{10} [/tex]
=》
[tex]work \: done = 600 \times 10[/tex]
=》
[tex]work \: done = 6000 \: \: joules[/tex]
B.)
[tex]work \: done = force \times displacement[/tex]
so,
=》
[tex]6000 = force \times10[/tex]
=》
[tex]force = \dfrac{6000}{10} [/tex]
=》
[tex]force = 600 \: \: Newtons[/tex]
The "Little Boy" nuclear bomb that was dropped on
Hiroshima had a yield of 6.9 x 10^13 J. In order to
release this much energy, kg of the uranium-
235 used in the bomb was converted into energy.
Answer:My gues is about 1/3 kg
Explanation:
I don't know physics
At what separation will two charges, each of magnitude 6.0 μC, exert a force of 0.70 N on
each other?
The two charges, each of magnitude 6.0 μC, exert a force of 0.70 N at separation of 1.47 meters.
What is electric force?Electric force is the attracting or repulsive interaction between any two charged things. Similar to any force, Newton's laws of motion describe how it affects the target body and how it does so. One of the many forces that affect objects is the electric force.
We know that electric force can be defined as:
Force: F = kQq/r²
0.70 = 9.0 × 10⁹ × (6.0×10⁻⁶)²/r²
r = 1.47 meter.
Hence, the separation between them is 1.47 meters.
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I cant solve this problem, and our teacher said that this would be in the test we'll have tomorrow, can someone help me?
A body of m = 6.8kg is launched with a speed of 7.5 m / s towards the top of an inclined plane of 15 ° with respect to the horizontal. in the absence of friction, what displacement does it make before reversing the direction of motion?
Answer:
d = 11.1 m
Explanation:
Since the inclined plane is frictionless, this is just a simple application of the conservation law of energy:
[tex] \frac{1}{2} m {v}^{2} = mgh[/tex]
Let d be the displacement along the inclined plane. Note that the height h in terms of d and the angle is as follows:
[tex] \sin(15) = \frac{h}{d} \\ or \: h = d \sin(15) [/tex]
Plugging this into the energy conservation equation and cancelling m, we get
[tex] {v}^{2} = 2gd \sin(15)[/tex]
Solving for d,
[tex]d = \frac{ {v}^{2} }{2g \sin(15) } = \frac{ {(7.5 \: \frac{m}{s}) }^{2} }{2(9.8 \: \frac{m}{ {s}^{2} })(0.259)} \\ = 11.1 \: m[/tex]
Q.2. Assertion: When distance between two bodies is doubled and also mass of each body is doubled. then the gravitational force between them remains the same. Reason: According to Newton's law of gravitation, force is directly proportional to the product of mass of the two bodies and inversely proportional to square of the distance between them. ent to
Answer:
True:
F1 = G M1 M2 / R^2
F2 = G (2 M1) * (2 M2) / (2 R)^2
F1 = F2
Pls help :(( I need help!! Its physics! motion and forces!
Answer: Pedaling your bike : acceleration :: applying the brakes : inertia.
The reason I think this to be the answer to the analogy is because there is energy and work used in both processes (and the unit focuses on forces); gravity is constant and does not change whether one pedals or applies brakes. And I do not think it's deceleration, as deceleration tends to equate to acceleration within the physics perspective.
Edit: I should also add that since you clarified that your unit is motion and forces, Newtons 1st law is the law of inertia. The way to change an objects motion for it to slow down is by applying an additional force. That resistance the bike experiences to slow is the process of inertia. Inertia happens in order to accelerate an object (either by slowing it down, or speeding it up): i.e., the resistance to change.