As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff springs arranged side by side so that they are parallel to each other. When you push the platform, you compress the springs. You do an amount of work of 76.0 J when you compress the springs a distance of 0.170 m from their uncompressed length.
(a) What magnitude of force must you apply to hold the platform in this position?
(b) How much additional work must you do to move the platform 0.200 m farther, and what maximum force must you apply?

Answers

Answer 1

Answer:

[tex]894.12\ \text{N}[/tex]

[tex]284.013\ \text{J}[/tex]

Explanation:

U = Energy = 76 J

x = Displacement of spring = 0.17 m

k = Spring constant

Energy is given by

[tex]U=\dfrac{1}{2}kx^2\\\Rightarrow k=\dfrac{2U}{x^2}\\\Rightarrow k=\dfrac{2\times 76}{0.17^2}\\\Rightarrow k=5259.51\ \text{Nm}[/tex]

Force is given by

[tex]F=kx\\\Rightarrow F=5259.51\times 0.17\\\Rightarrow F=894.12\ \text{N}[/tex]

The magnitude of force must you apply to hold the platform is [tex]894.12\ \text{N}[/tex].

Now [tex]x=0.17+0.2=0.37\ \text{m}[/tex]

[tex]U=\dfrac{1}{2}kx^2\\\Rightarrow U=\dfrac{1}{2}\times 5259.51\times 0.37^2\\\Rightarrow U=360.013\ \text{J}[/tex]

Additional energy

[tex]360.013-76=284.013\ \text{J}[/tex]


Related Questions

A car starting from rest is accelerated uniformly to a velocity of 100.8km/h. Convert this to metre per secondphy​

Answers

Explanation:

100.8 km/h × (1000 m/km) × (1 h / 3600 s) = 28 m/s

Answer:

28 m/s

Explanation:

100.8km/hr * 1hr/3600sec* 1000m/km= 100.8*1000/3600 m/s

A diagram of a plant cell is shown below.
Which organelle is found in both plant and animal cells?
Cell membrane
Chloroplast
Ο Ο Ο
Large Vacuole
Cell Wall

Answers

Answer:

The Cell Membrane is found in both plant and animal cells.

Explanation:

Chloroplast, Large Vacuole and Cell Wall are all found in plant cells.

Assume a uniformly charged ring of radius R and charge Q produces an electric field Ering at a point P on its axis, at distance x away from the center of the ring. Now the charge Q is spread uniformly over the circular area the ring encloses, forming a flat disk of charge with the same radius. How does the field Edisk produced by the disk at P compare to the field produced by the ring at the same point?Assume a uniformly charged ring of radius R and charge Q produces an electric field Ering at a point P on its axis, at distance x away from the center of the ring. Now the charge Q is spread uniformly over the circular area the ring encloses, forming a flat disk of charge with the same radius. How does the field Edisk produced by the disk at P compare to the field produced by the ring at the same point?

Answers

Answer:

* E_ring = [tex]k \ \frac{x}{(x^2+ y^2)^{3/2} } \ Q[/tex]

*E_ disk= 2kQ  [tex]\frac{1}{R^2} \ (1 - \frac{x}{(x^2+ R^2)^{1/2} } )[/tex]

Explanation:

Let's start by finding the electric field of the charged ring

in the attachment we can see a diagram of the system. Due to circular symmetry, the electric field perpendicular to the axis is canceled and only the electric field remains parallel to the axis.

            Eₓ = E cos θ          (1)

            E = k ∫  [tex]\frac{dq}{r^2}[/tex]

            cos θ = x / r

             

using the Pythagorean theorem

            r = [tex]\sqrt{x^2 + y^2}[/tex]

we substitute

            Eₓ = k ∫ [tex]\frac{dq}{x^2+y^2} \ \frac{x}{\sqrt{ x^2+y^2} }[/tex]

            Eₓ =  [tex]k \frac{x}{(c^2+y^2)^{3/2} }[/tex]   ∫ dq

             Eₓ = k \frac{x}{(c^2+y^2)^{3/2} }  Q

the ring's electric field

             E_ring = [tex]k \ \frac{x}{(x^2+ y^2)^{3/2} } \ Q[/tex]

Now let's find the electric field of the disk

The charge is distributed over the entire disk, so let's use the concept of charge density

              σ = [tex]\frac{dq}{dA}[/tex]

Let's approximate the disk as a group of rings, the width of each ring is dr, the area is

              dA = 2πr dr

               

we substitute

             σ = [tex]\frac{1}{2\pi r} \ \frac{dq}{dr}[/tex]

             dq = 2π σ r dr

we substitute in equation 1, where the electrioc field is of each ring

             Eₓ = [tex]k \int\limits^R_0 \ { \frac{x}{(x^2+r^2)^{3/2} } \ 2\pi \sigma \ r } \, dr[/tex]

             

if we use a change of variable

               dv = 2rdr

               v = r²

              Eₓ =  [tex]k x \pi \sigma \int\limits^a_b { \frac{1}{(x^2+v)^{3/2} } } \, dv[/tex]

we integrate

              Eₓ = k x π σ   [tex][ \frac{ (x^2 + r^2)^{-1/2} }{-1/2} ][/tex]

we value in the limits from r = 0 to r = R

              Eₓ = k π σ x  (-2) [ [tex]\frac{1}{ \sqrt{x^2+R^2} } - \frac{1}{x}[/tex]]

              Eₓ = 2π k  σ ([tex]1 - \frac{x}{(x^2 + R^2 ) ^{1/2} }[/tex]  )

 

             σ = Q/πR²

substitute

             Eₓ = 2 k Q/R² (1 - \frac{x}{(x^2 + R^2 ) ^{1/2} } )

             E_ disk= 2kQ  [tex]\frac{1}{R^2} \ (1 - \frac{x}{(x^2+ R^2)^{1/2} } )[/tex]

             

The two electric fields are

* E_ring = [tex]k \ \frac{x}{(x^2+ y^2)^{3/2} } \ Q[/tex]

*E_ disk= 2kQ  [tex]\frac{1}{R^2} \ (1 - \frac{x}{(x^2+ R^2)^{1/2} } )[/tex]

we can see that the functional relationship of the two fields is different

PLEASE HELP
The spine is part of which system?
A. Circulatory System
B. Central Nervous System
C. Endocrine System

Answers

Answer:

Explanation:

B. Central Nervous System

3. A backpack weighs 8.2 N and has a mass of 5 kg on the moon. What is t
strength of gravity on the moon?
8.2 N

Answers

Weight is equivalent to the product of the mass of an object and the strength of the gravitational field.

Using:
F = ma

a = 8.2 / 5
a = 1.64 N/kg

The gravitational field strength is equivalent to 1.64 N/kg.


[tex]2(2 \times 5) [/tex]

Answers

20, as you do the brackets first:
2x5=10
10x2=20

Answer:

20

Explanation:

→ First perform calculation within brackets

2 × 5 = 10

→ Resubstitute back

2 × 10

→ Solve

20

What does efficient mean in your own words in science

Answers

Answer:

Efficient means something that gives 100% accuracy.

What is a simple circuit?​

Answers

Answer:

This is your answer. If I'm right so,

Please mark me as brainliest. thanks!!

Answer:

A simple circuit definition is a closed loop of a conductor that electrons can travel around, usually consisting of a power source (a battery, for example) and an electrical component or device (like a resistor or a light bulb) and conducting wire.

Outline 3 disadvantages and advantage of water and alcohol as a template liquid​

Answers

Answer:

Advantages of mercury as a thermometric liquid.

-It is a good conductor of heat and therefore the whole liquid reaches the temperature of the surroundings quickly.

-It does not wet (cling to the sides of) the tube.

-It has a high boiling point

-It expands uniformly (linear expansion) and responds quickly to temperature changes, hence is sensitive.

-It has a visible meniscus.

Disadvantages

-Mercury is very poisonous.

-its expansively is fairly low

-it is expensive

-It has a high freezing point therefore it cannot be used in places where the temperature gets very low.

Alcohol has a thermometric fluid

-Alcohol expands uniformly.

-It has a low freezing point (-115 degreecentigrade) therefore it is very suitable for place where the temperature gets very low.

-It has a large expansively

-It is an easily available cheap liquid, which is safe to use

Disadvantages of alcohol

-it wets the tube

-it has a low boiling point (cannot be used in places with high temperatures)

-it does not react quickly to changes in temperature

-It needs to be dyed, since it's colourless.

Disadvantages of water

-Water has high specific heat capacity. So it cannot be used for measuring small temperature differences.

- Water will wet the surface of the glass tube. It is a sticky substance.

- Water is transparent

Explanation:

11. There are 2 main reasons geologists think the continents were once connected. One
reason is that some coastlines share similar fossils. What is the other reason? II

Answers

Answer:

they all kinda fit together like a puzzle also because they can tell now that the continates are moving so, they can asume that they have always been moving

10. A 50 kg bicyclist on a 10 kg bicycle speeds up from 5.0 m/s to 10 m/s.
(a) What was the total kinetic energy before accelerating? Full working out​

Answers

Answer:

T.K.E = 750 Joules.

Explanation:

Given the following data;

Initial velocity, u = 5m/s

Final velocity, v = 10m/s

Mass of bicyclist = 50kg

Mass of bicycle = 10kg

Total mass, Tm = 50 + 10 = 60kg

Kinetic energy can be defined as an energy possessed by an object or body due to its motion.

Mathematically, kinetic energy is given by the formula;

[tex] K.E = \frac{1}{2}mv^{2}[/tex]

Where;

K.E represents kinetic energy measured in Joules.

m represents mass measured in kilograms.

v represents velocity measured in metres per seconds square.

To find the total kinetic energy before accelerating simply means the kinetic energy due to the initial velocity and total mass;

[tex] T.K.E = \frac{1}{2}T_{m}U^{2}[/tex]

Substituting into the equation, we have;

[tex] T.K.E = \frac{1}{2}*60*5^{2}[/tex]

[tex] T.K.E = 30*25 [/tex]

T.K.E = 750 Joules.

The provided text reads: "a typical lightning bolt may transfer 10^20 electrons in a fraction of a second, developing a peak current of up to 10 kiloamperes." Using the value of the elementary charge of 1.6x10^-19 C We can estimate the total charge of the lightning bolt to be about *
1.6E1 C
1.6E4 C
1.6E10 C
1.6E20 C

Answers

Answer:

1.6e20

Explanation:

what is agrculture and it means​

Answers

Answer:

Agriculture is the science, the practice of cultivating the soil, art, producing crops, raising livestock, and in varying degrees the preparation and marketing of the resulting products cleared the land to use for agriculture.

Explanation:

This is what I found during my research and I hope this helps. Correct me if I am incorrect! Have a good one.

≧◉◡◉≦

how is sound produced by using pipel wind instruments​

Answers

The air inside the pipes of a wind instrument vibrates. ... The result is longitudinal standing waves in the air column inside the pipe. The ends, whether open or closed, create nodes or antinodes in these standing waves.

Answer33

Explanation

33

When the frequency of a sound wave is doubled, then:

Answers

Answer:

If the frequency of a wave is doubled, what happens to its wavelength? If the frequency is doubled, the wavelength is only half as long.

Answer:

Hey,

QUESTION)

✔ We have : λ = v/f

According to this relationship, the wavelength is inversely proportional to the frequency. So when the frequency doubles, the wavelength is halved.

Two objects A and B (both masses are m) are connected by a spring of elastic constant k and placed on a frictionless surface. At some point, A gains an initial velocity v parallel to the spring, and this system will thus start moving. Knowing that the spring is undeformed in the beginning, determine (a) the highest elastic potential energy that can be stored in the spring and (b) the highest velocity that can be reached by B.

Answers

Answer:

a)   Em_f = ½ m vₐ²,  b)    v = vₐ /√2

Explanation:

a) For this part we use conservation of energy

   starting point .. block A moving, spring unstretched

          Em₀ = K = ½ m vₐ²

end point. Stretched spring

          Em_f = K_e = ½ k x²

energy is conserved

          Em₀ = Em_f

          Em_f = ½ m vₐ²

b) Let's analyze the movement a little, block A began to move at a speed va, I stretch the spring an amount Dx, it exerts a force on block b that begins to move and the elongation of the spring decreases.

In all this process there is no friction force, therefore the energy is conserved, therefore the maximum energy stored in the spring must be distributed among the bodies.

           Em₀ = K_e = E₀

where E₀ is the initial energy of block a

            E₀ = ½ m vₐ²

At the point where we are in equilibrium

          Em_f = Kₐ + K_b = ½ m vₐ² +1/2 m [tex]v_{b}^2[/tex]

so that the spring does not stretch or shrink, the two bodies must go at the same speed.

          Em_f = m v²

energy is conserved

          Em₀ = Em_f

          ½ m vₐ² = m v²

           v = vₐ /√2

therefore both blocks must go at this speed

describe how electrons create electricity

Answers

describe how electrons create electricity

Atoms are made up of even smaller elements, called protons, electrons and neutrons. When electrical and magnetic forces move electrons from one atom to another, an electrical current is formed

Electrons in atoms can act as our charge carrier, because every electron carries a negative charge. If we can free an electron from an atom and force it to move, we can create electricity. ... In its balanced state, copper has 29 protons in its nucleus and an equal number of electrons orbiting around it.

Hope It Helps!

What is the rarefaction of a longitudinal
wave?
A. the place where the particles are closest together
B. the place where the particles are farthest apart
C. the resting position of the wave
D. how fast the parts of the wave move
Sea

Answers

The answer Is B! Good luck

Noah Formula is riding an old-fashioned roller coaster. Noah encounters a small hill having a radius of curvature of 12.0 m. At the crest of the hill, Noah is lifted off his seat and held in the car by the safety bar. If Noah is traveling with a speed of 14.0 m/s, then use Newton's second law to determine the force applied by the safety bar upon Noah's 80-kg body.'

Answers

Answer:

1306.66N

Explanation:

Given data

r=12.0 m

v=14 m/s

m= 80kg

From the formula

F= mv^2/r

substitute

F= 80*14^2/12

F= 80*196/ 12

F= 15680/12

F=1306.66N

Hence the force applied is 1306.66N

A 70 ft rope hangs from a helicopter above this room. The rope has a mass per unit length of 2 lb/ft. In order to be rescued from this exam the helicopter must pull you up and out of the room to safety. Assume that you weigh 120 lbs. How much work will it take get you safely away from this test

Answers

Answer:

The work done to get you safely away from the test is  2.47 X 10⁴ J.

Explanation:

Given;

length of the rope, L = 70 ft

mass per unit length of the rope, μ = 2 lb/ft

your mass, W = 120 lbs

mass of the 70 ft rope  = 2 lb/ft x 70 ft

                                         = 140 lbs.

Total mass to be pulled to the helicopter, M = 120 lbs  + 140 lbs  

                                                                       = 260 lbs

The work done is calculated from work-energy theorem as follows;

W = Mgh

where;

g is acceleration due gravity = 32.17 ft/s²

h is height the total mass is raised = length of the rope = 70 ft

W = 260 Lb x 32.17 ft/s²  x 70 ft

W = 585494 lb.ft²/s²

1 lb.ft²/s² = 0.0421 J

W = 585494 lb.ft²/s²  = 2.47 X 10⁴ J.

Therefore, the work done to get you safely away from the test is  2.47 X 10⁴ J.

Everything is made of tiny atoms. Each of these atoms is made up of a core that has a positive charge, and some electrons that circle around the core. These have a negative charge. When these electrons move around in a substance and between substances, an _______________ is created.

even charge

uneven charge

plsssssssssss answer correct i am not trying to be mean but correct answers only plsssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss

Answers

Answer:

uneven

Explanation: :)

Answer:

uneven charge, b

Explanation:

If an engine cannot be 100%
efficient, what happens to the
energy that is lost?
A. It disappears.
B. It reproduces.
C. It still exists, but in a different form.

Answers

Answer: Given the evidence in the explanation, I'm pretty sure it's C. It still exists, but in a different form.

Explanation: "Some part of the energy supplied is used to change the internal energy of the system. Some part is also released into the surroundings. Generally, frictional losses are more predominant for the machines being not 100% efficient. This friction leads to the loss of energy in the form of heat, into the surroundings."

The answer is C hope this helps

what is the magnitude of electric field at apoint 2 meter from a point charge q= 4nc​

Answers

i do not have a clue i need to answer so i can ask questions sorry

1. An astronaut is getting ready to explore. If his mass is 60 kg, what is his weight
on Earth?

Answers

60*2.2=132lbs ...........

Which is a primary energy source used by power plants to generate electricity?
coal
O wood
o gasoline
batteries

Answers

Answer:

Your answer is wood that is what they used

The primary energy source used by power plants to generate electricity is coal.

What are power plants?

Power plants are plants which use fuels to generate electricity for use by homes and industries.

Power plants have different energy sources for their fuel.

The primary energy source used by power plants to generate electricity is coal.

Therefore, coal is a primary source of fuel for power plants.

Learn more about power plants at: https://brainly.com/question/16064039

#SPJ6

A child swings with a small amplitude on a playground with a 2.5m long chain.
a) what is the period of the child’s motion
b) what is the frequency of vibration

Answers

a) T=2*pi(L/g)^1/2
T=2*3.14(2.5/9.81)^1/2
T=3.171s
b) T=1/f
f=1/3.171
f=0.315Hz

a. The period of the child's motion is 3.171 seconds.

b. The frequency of the vibration is 0.315 Hz.

Calculation of the period & frequency:

Since A child swings with a small amplitude on a playground with a 2.5m long chain.

a. So here the time period should be

[tex]2\times \ pi(L/g)^{1/2}\\\\2\times 3.14(2.5/9.81)^{1/2}[/tex]

T=3.171s

b) Now the frequency is

[tex]T=1\div f\\\\f=1\div 3.171[/tex]

f=0.315Hz

learn more about frequency here: https://brainly.com/question/22971850

An organ pipe closed at one end is 0.76 m long. (A) Determine its fundamental frequency. (B) What are the 3rd and 5th harmonics? Note: Use 344 m/s as the speed of sound.

Answers

Answer:

A) 113.16 Hz

B) 339.47 Hz

565.79 Hz

Explanation:

Only odd harmonics are present in closed pipes that was why they asked for 3rd and 5th harmonics.

Choose five chemical changes from the list below.

running in place
dropping a glass
rotting milk
apples getting ripe
smashing a rock
digesting your lunch
burning paper
cutting up an apple
iron rusting

Answers

iron rusting, burning paper, rotting milk, digesting your lunch, and apples getting ripe:)) hope this help pls mark me branliest!!<3

An 80 N force causes a spring to compress 0.15 m. What is the spring constant? What is the potential energy of the spring?

Answers

The spring constant of the given spring is= -533.33

The potential energy of the spring= 6 Joule

What is force?

A push or pull that causes object to change its state of rest or motion.

It can also change the direction of a moving body.Force is a product of mass and acceleration.

For spring;

K is the spring constant.

         ⇒Force = -kx

         ⇒80N=0.15m ×-k

          ⇒K=-80/0.15

          ⇒K= -533.333

So the spring constant is 533.333

Potential Energy=1/2kx²

                            ⇒0.5×533.33 ×0.15×0.15

                            ⇒5.95.99 N

Learn more about force here: http://brainly.com/question/25239010

#SPJ2

Which on the map
represents Asia?

Answers

Answer:

B because it's on Asia but that pfp tho

The answer is B that represents Asia
Other Questions
Can somebody help me with that? "Sousa was the greatest musical star of his era, combining the charismaand popularity of Leonard Bernstein and the Beatles."Which statement identifies a weakness in the supporting evidence forthe author's opinion?A. The author does not compare Sousa to musicians of the sameera.B. The author does not consider qualifications other thanpopularity.C. The author does not explain what qualified Sousa as the greateststar.D. The author does not include other writer's opinions. When writing a story, do you italicize the names of brands such as Disney+? Does the idea of a flexible work arrangement appeal to you? Why or why not? 2. Kiko is a ninja warrior trained by Mountain Master Yoho Mahrati.When Master Mahrati is slain by Shan Bhutan of the Lotus Clan in themost cowardly of fashions, Kiko lays it all on the line to avenge thedeath of his master. Will Kiko overcome Shan Bhutan and the powerfulLotus Clan?Protagonist:Antagonist:Type of Conflict: Hello can someone help me with this please f(x) = - 4x ^ 2 + 4x - 4 Find f(3)Need help WILL GIVE BRAINLIEST True or false The inventor of the first crossbow owned the invention? If 3 x/4 +2 =56.8, what is the value of x?A) x 2.891B) x 6.708C) x 4.323D) x 2.059 Paco is trying to explain to his friend that 7 divided by 2 is 7/2 draw a model or number line showing 7 divided by 2 = 7/2 Please I need help filling in the blanks 10A cone has a volume of 98 cm.The radius of the cone is 5.13 cm.Work out an estimate for the height of the cone. In a market economy, prices are determined by supply and demand. How is the price of an item affected if the supply goes down? A. The price of the item will go down. B. The price of the item will stay the same. C. The price of the item will go up. D. The price will go down, but then it will go up. um- answer and explanation please VerbosComplete the chart with the correct verb forms.Infinitivocontar(3)mostrarMeett(1)juegas(5)empiezasnosotrascontamos(4)mostramos(8)ellos(2)juegan(6)empiezan(2) What is humanism? What are the main ideas within humanism? n=1 (n^2n)/(1+n)^(3n) Does it converge or diverge?What method did you use?PLEASE HELP If you had been a delegate at the Congress, do you think you would have been a conservative or radical? Why? herlp mehhhh pweeaasee!!!! Where is the perseverance rover scheduled to land on MarsGale CreterJezero CraterHolden CreteVictoria Crater