Answer:
1) correct answer is ii larger size
2) false, 3) false, 4) true, 5) true, 6) true
Explanation:
In this exercise, the answer is asked if the statement is true.
1) in the rapid cooling speed, there is no thermodynamic equilibrium, so the secondary phases do not have time to transform into the main one, therefore many phases appear in the products,
the correct answer is ii
2) False. The transformation of a material to the glass state requires a fixed temperature and rapid changes to reach this temperature,
3) False. The most stable state is the crystalline state, the glass states are metastable, their Gibbs energy is not the lowest possible and they must transition to the crystalline state over time, it can be years or centuries.
4) True. The melting and freezing temperatures change for each material, within the same material it always has the same value, since it corresponds to a change in the state of the system.
5) true. Cast iron is called gray because of the impurities inside that have not had time to move due to rapid cooling.
6) True. The microstructure is reduced in the process of cooling and heating
when there is a constant unbalanced force applied in the opposite direction as the motion what will happen to speed and acceleration
Answer:
speed will be constant and so no acceleration
Explanation:
the body will move toward the weaker force, but since the forces are constant there will be no acceleration.
How much heat is given off when 210.0 g of water at 0°C freezes into ice?
Answer:
it gives off 71.0 kJ of heat.
Explanation:
The earth completes a circular orbit around the sun in one year. The orbit has a radius of 93,000,000 miles. What is the speed of the earth around the sun in m/s?
Report your result using scientific notation and the correct significant figures.
—x10–m/s
In a year, the earth revolves around the sun once in a circular motion. Therefore, the earth will orbit the sun at a 2.95 m/s speed.
Planets in our solar system did not appear out of thin air. Neither did the sun. They were all a part of a large cloud of gas and dust. Gravity accumulated a lot of material in the center to form the sun. As it spun around the forming sun, the extra matter clashed and gathered together. Some would be capable of attracting more gas and dust, eventually forming planets, because to their powerful gravitational forces.
The answer to the query is
v = 2πR / T
2R equals 6.28 * 9.3 * 107 miles.
T = 24 * 3600 * 365 = 3.15 × 10⁷ sec
v = 9.3 / 3.15 = 2.95 m/s.
Hence, the earth's speed of the earth around the sun will be 2.95 m/s.
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Define the following
a. Velocity:
b. Inertia:
c.Speed:
e Force:
f. Balanced force:
g. Net force:
h. Displacement:
Answer:
Explanation:
a.speed with direction associated
b.the ability to resist motion
c.The rate of change of position of an object
e.any influence object's motion
f.forces cancel out, create equilibrium
g.total force acting on an object
h. change in position of an object (total distance from starting point)
Which of the following factors affects the strength of the gravitational force between two objects?
Answer: The distance between the objects
Explanation:
Two springs have spring constants of 10.0 N/cm and 15.0 N/cm. Which spring is more difficult to stretch
The spring with the higher spring constant (15.0 N/cm) will be more difficult to stretch than the spring with the lower spring constant (10.0 N/cm).
This is because the spring constant is directly related to the amount of force required to stretch the spring. Therefore, the higher the spring constant, the more force that is required to stretch the spring.
The spring constant is a measure of how difficult it is to stretch or compress a spring. It is determined by the stiffness of the spring material, its shape and size, and how much the spring is compressed or stretched.
The higher the spring constant, the more force is required to stretch or compress the spring. The lower the spring constant, the less force is required to stretch or compress the spring.
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Why are dynamic flexibility tests not used as often as?
Dynamic flexibility tests are not used as often as static flexibility tests because dynamic flexibility tests involve more subjective measurements.
Static flexibility tests are more common in comparison to dynamic tests because static flexibility tests are easier to replicate. It is difficult to standardize motion-based tests such as dynamic flexibility tests between various subjects, while static flexibility tests are simple and easy to standardize it is because the metrics are fixed and not open to interpretation.
Since, dynamic flexibility tests are hard to perform because they measure the amount of stress on a muscle that is in motion. And it is difficult to assess this among multiple people and to get an accurate picture. That is why these tests are not used as often as static flexibility tests.
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Complete question
Why are dynamic flexibility tests not used as often as static flexibility tests?
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You are on an airplane traveling with a constant velocity at an altitude of 20,000 m. What is the acceleration of gravity at that altitude
Correct option is C) the acceleration of gravity at that altitude is 9.75m/s².
What is the gravity's acceleration?
The unit g stands for gravitational acceleration. At sea level, the standard value of g on earth's surface is 9.8 m/s2.
The following formula is used to determine the acceleration of gravity:
g= GM/r2
What G The general gravitational constant is what it is.
G is equal to 6.674x10⁻¹¹ Nm2/kg2, and M is the earth's mass:
M = 5.972x10²⁴kg
The radius of the earth plus the airplane's altitude, or r, is the distance from the earth's center in this case:
r = 6.37x10⁶ m + 20000 m equals 6.39x10⁶ m
Consequently, the acceleration in g is equal to:
(6.674x10⁻¹¹ Nm²/kg²)(5.972x10²⁴ kg) / (6.39x100m)₂
g = 9.75m/s²
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Complete Question -
You are on an airplane traveling with a constant velocity at an altitude of 20,000m. What is the acceleration of gravity at that altitude? The earth's radius is 6.37 x 10^6m.. . A) 9.81 m/s^2. B) 9.78 m/s^2. C) 9.75 m/s^2. D) 9.72 m/s^2. E) 9.69 m/s^2.
How are displacements combined?
Make meaurement and calculation to predict where the puck will land and whether the puck will land on Eintein or not. Upload or decribe all the tep you took to anwer thi. Include the meaurement you made from thi video, the equation you ued and the final reult
In the given case it can be concluded that- The two basic tenets of the special theory of relativity were that observers moving at constant speeds should be subject to the same physical rules and that the speed of light is constant for all observers.
According to Small amounts of mass (m) can be substituted for huge amounts of energy according to the theory, which uses the speed of light to establish the link between energy and matter (E), Einstein's general theory of relativity from 1915, the spacetime curvature is what causes what we experience as the gravitational force.Relativity ushered in the nuclear era while advancing our understanding of elementary particles and their basic interactions in the field of physics. Relativity made it possible for cosmology and astrophysics to predict unusual celestial phenomena like neutron stars, black holes, and gravitational waves.To know more about theory of relativity here
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The film strip that emerges from the camera is usually a ______________. That is, its color and light values are the opposite of those in the original scene.
The film strip that emerges from the camera is usually a Negative. That is, its color and light values are the opposite of those in the original scene.
What controls how much light enters the camera?One of the three camera settings that affects exposure is the aperture. The shutter speed, aperture, and ISO settings are together referred as as the "exposure triangle." By adjusting the relative amount of light entering a camera lens, an aperture can change the exposure.
What part of the camera and eye controls how much light enters?A camera's shutter can close or open depending on how much light is required to expose the film at the rear of the device.
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Which best describes a chemical reaction with accompanying absorption of heat?
Endothermic Reactions
Answer:
Chemical reactions that release energy are called exothermic. ... Chemical reactions that absorb (or use) energy are called endothermic. In endothermic reactions, more energy is absorbed when the bonds in the reactants are broken than is released when new bonds are formed in the products.
Explanation:
Endothermic reactions are ones that absorb heat energy. The excess heat absorbed in the reaction is being used to break bonds in the products. One of the most obvious types of endothermic reaction is the melting of ice. Endothermic Processes
These examples could be written as chemical reactions, but are more generally considered to be endothermic or heat-absorbing processes: Melting ice cubes. Melting solid salts. Evaporating liquid water
How do icebergs form in saltwater?
An iceberg is formed by the broken part of a large glacier that floats into the sea. The iceberg is composed of fresh water, just like the glaciers or ice in the North Pole. Since, freshwater is less thick than salty seawater, icebergs float in the water.
When chunks of ice break off the end of a glacier that is flowing into ocean, icebergs are created.
Since, seawater has a slightly higher density than ice, the iceberg floats with the majority of its mass below the surface. A cork, on the other hand, floats quite near to the water's surface due to its density, which is around 20% that of water.
As moving icebergs are dangerous, they have never been a main supply of drinking water. Freshwater is released by melting glaciers and icebergs, which also lowers the salinity of the surrounding sea.
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Define the following
a. Length:
b. Density:
c.Mass:
d. Volume:
e Standard:
Answer:
a.the measurement or extent of something from end to end; the greater of two or the greatest of three dimensions of a body.
b.is the measurement of how tightly a material is packed together. It is defined as the mass per unit volume.
c.Mass is a physical magnitude and general property of matter that expresses the inertia or resistance to change in motion of a body.
d.Mass is a physical magnitude and general property of matter that expresses the inertia or resistance to change in motion of a body.
e.
Which of the following conditions should be met to make a process perfectly reversible?
Check all that apply.
(1) Any mechanical interactions taking place in the process should be frictionless.
(2) Any thermal interactions taking place in the process should occur across infinitesimal temperature or pressure gradients.
(3) The system should not be close to equilibrium.
1) Any mechanical interactions taking place in the process should be frictionless, to make a process perfectly reversible
What is mechanical interactions?
Mechanical interactions are physical forces that are used to affect the behavior of objects and materials. This can include contact forces such as friction, tension, and compression, as well as non-contact forces such as gravity, magnetism, and electric fields
Mechanical interactions can be used to cause objects to move, change shape, or experience a change in energy. These interactions can also be used to create, store, or transfer energy. Mechanical interactions are studied by engineers and scientists in multiple disciplines, and are used in many different applications, including the design of machinery, medical devices, and consumer products.
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Construct the following SI derived unit, the coulomb, and define the faraday. A coulomb is a measure of and has units of: 1 A faraday is a constant and has a value of: (include units)
A coulomb is a measure of electrical charge and has units of amperes times seconds (A⋅s). A faraday is a constant equal to the magnitude of electric charge per mole of electrons of 96,485.3399 Coulombs (C).
What is magnitude?
Magnitude is a measure of the size or scale of an object or event. It is often used to describe the intensity or severity of a phenomenon, such as earthquakes and hurricanes. It is usually expressed as a number on a logarithmic scale. In astronomy, magnitude is used to measure the brightness of stars and other celestial bodies. On Earth, magnitude is often used to measure the size of earthquakes and other seismic events. Magnitudes are typically expressed as a number on a logarithmic scale, with a greater magnitude indicating a larger size or scale of the event. Magnitudes can also be used to measure the intensity of light, sound, and other forms of energy.
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What is the contribution of hydroelectric power in world electricity?
Hydroelectric power accounts for between 16 and 17 percent of global electricity production, making it one of the most significant renewable energy sources.
In 2016, hydropower contributed more than twice as much to the grid as the next largest renewable energy source, solar. Hydropower can provide many valuable services to the power grid beyond just energy generation. These include frequency regulation, voltage support, contingency reserves, load following, and black start service, all of which contribute to the reliability and safety of the power system. Hydropower's role in grid-scale energy storage, balancing services for other intermittent renewables like wind and solar power, and water management services by reservoirs are growing.
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A long string is stretched and its left end is oscillated upward and downward. Two points on the string are labeled A and B. Points A and B are indicated on the string. Orient the two vectors, vA-> and vB-> to correctly represent the direction of the wave velocity at points A and B. rotate the given vectors to indicate the direction of the wave velocity at the indicated points. (Please draw a picture of the end result)
A lengthy string is simple to stretch. The string's two designated spots, A and B, should be at an angle of 90 degrees with the same magnitude, and B should be at an angle of 270 degrees with the same magnitude.
Angle magnitude definition
This is referred to as the amount of rotation that is believed to have been applied to one of the arms' vertex in order to produce a specific position for the other.
It is well known that equal vectors have the same magnitude and direction. When the magnitude and direction of two vectors are the same, they are said to be equal.
|v|=a2+b2 yields the magnitude. Depending on the application, the direction is equal to the angle made with the x-axis or the y-axis.
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For the circuit in the attached plot, find the energy stored in the capacitor under DC conditions. O 30 mJ O 3 mJ O 0.045 mJ O 0.005 mJ
The energy stored in the capacitor is 0.045 mJ. Under DC conditions, the capacitors will be open-circuited.
What is the formula for energy stored in a capacitor?Energy stored in a capacitor can be calculated by
E = ½ CV²
Where
E = energy (J)C = capacitance (F)V = voltage (V)The picture of circuit in the attached plot is in the attachment.
Find the energy stored in the capacitor under DC conditions!
We have
R₁ = 10 ΩR₂ = 20 ΩC = 0.1 μFI = 3 AUnder DC (Direct Current) conditions, the capacitors will be open-circuited. It means that there is no current will flow through the 20 Ω resistor. So, I across the 10 Ω resistor is the same as I source.
See the picture below in the attachment!
The voltage across the 10 Ω resistor is
V = IR
V = 3(10)
V = 30 V
The voltage across the capacitor is the same as the voltage across the 10 Ω resistor.
Vc = V = 30 V
The energy stored would be
E = ½ C Vc²
E = ½ (0.1)(10⁻⁶)(30)²
E = ½ (10⁻⁷)(900)
E = 450 × 10⁻⁷
E = 0.045 × 10⁻³
E = 0.045 mJ
Hence, the energy stored in the capacitor under DC conditions is 0.045 mJ. The correct option is (c).
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What is the difference between active and passive flexibility?
The difference between active flexibility and passive flexibility is that in active flexibility, we rely on our own muscle power to reach the end range, but in passive flexibility, we rely on an external push to reach the end range.
According to the findings of recent studies, active flexibility has a stronger connection to a person's level of sporting performance than passive flexibility does. The ability to build active flexibility is more difficult to achieve than passive flexibility. Active flexibility involves passive flexibility in addition to muscle strength in order to be able to retain and maintain the initial extended position.
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PLSS HELP!! Are these True or False questions
Answer:
11. True
12. False (air pressure)
13. False (nitrogen)
14. False (stratosphere)
Explanation:
The acceleration of a motorcycle is given by ax(t)=At-Bt2,A=1.5m/s2,B=0.120m/s2,the motorcycle at rest at t=0 a)Find its position and velocity as function of time b)What maximum velocity it attains
Answer:
(a)
[tex]v(t) = \frac{At^2}{2} -\frac{Bt^3}{3}[/tex] --- velocity
[tex]x(t) = \frac{At^3}{6} -\frac{Bt^4}{12} + x(0)[/tex] --- position
(b) The maximum velocity is: 39.0625m/s
Explanation:
Given
[tex]a_x(t) =At -Bt^2[/tex]
[tex]A = 1.5m/s^3[/tex]
[tex]B = 0.120m/s^4[/tex]
Solving (a): The position and velocity as a function
To calculate the change in velocity, we integrate the given acceleration
i.e.
[tex]\int\limits^{v(t)}_{v(0)} {dv} = \int\limits^t_0 {a(t)} \, dt[/tex]
Integrate
[tex]v|\limits^{v(t)}_{v(0)} = \int\limits^t_0 {a(t)} \, dt[/tex]
Substitute v(t) and v(0) for v
[tex]v(t) - v(0) = \int\limits^t_0 {a(t)} \, dt[/tex]
[tex]v(0) = 0[/tex] ---- The initial velocity.
So, we have:
[tex]v(t) - 0 = \int\limits^t_0 {a(t)} \, dt[/tex]
[tex]v(t) = \int\limits^t_0 {a(t)} \, dt[/tex]
Substitute: [tex]a_x(t) =At -Bt^2[/tex]
[tex]v(t) = \int\limits^t_0 {[At -Bt^2]} \, dt[/tex]
Integrate
[tex]v(t) = {\frac{At^2}{2} -\frac{Bt^3}{3}}|\limits^t_0[/tex]
Substitute 0 and t for t
[tex]v(t) = [\frac{At^2}{2} -\frac{Bt^3}{3}] - [\frac{A*0^2}{2} -\frac{B*0^3}{3}][/tex]
[tex]v(t) = [\frac{At^2}{2} -\frac{Bt^3}{3}] - 0[/tex]
[tex]v(t) = \frac{At^2}{2} -\frac{Bt^3}{3}[/tex]
To calculate the change in position, we integrate the calculated velocity
i.e.
[tex]\int\limits^{x(t)}_{x(0)} {dx} = \int\limits^t_0 {v(t)} \, dt[/tex]
Integrate
[tex]x(t)|\limits^{x(t)}_{x(0)} = \int\limits^t_0 {v(t)} \, dt[/tex]
Substitute x(t) and x(0) for x(t)
[tex]x(t) - x(0) = \int\limits^t_0 {v(t)} \, dt[/tex]
Substitute: [tex]v(t) = \frac{At^2}{2} -\frac{Bt^3}{3}[/tex]
[tex]x(t) - x(0) = \int\limits^t_0 {\frac{At^2}{2} -\frac{Bt^3}{3}} \, dt[/tex]
Integrate
[tex]x(t) - x(0) = \frac{At^3}{6} -\frac{Bt^4}{12}}|\limits^t_0[/tex]
Substitute t and 0 for t
[tex]x(t) - x(0) = [\frac{At^3}{6} -\frac{Bt^4}{12}] - [\frac{A*0^3}{6} -\frac{B*0^4}{12}][/tex]
[tex]x(t) - x(0) = [\frac{At^3}{6} -\frac{Bt^4}{12}] - [0][/tex]
[tex]x(t) - x(0) = \frac{At^3}{6} -\frac{Bt^4}{12}[/tex]
Make x(t) the subject
[tex]x(t) = \frac{At^3}{6} -\frac{Bt^4}{12} + x(0)[/tex]
Where x(0) represents the initial position
Solving (b): The maximum velocity
First, we calculate the time at which it attains the maximum height
Set acceleration to 0
[tex]a_x(t) =At -Bt^2[/tex]
[tex]At - Bt^2 = 0[/tex]
Factorize
[tex]t(A - Bt) = 0[/tex]
Split
[tex]t = 0\ or\ A - Bt = 0[/tex]
t can't be 0.
So, we have:
[tex]A - Bt = 0[/tex]
Solve for t
[tex]-Bt = -A[/tex]
[tex]t = \frac{-A}{-B}[/tex]
[tex]t = \frac{A}{B}[/tex]
Substitute: [tex]A = 1.5m/s^3[/tex] and [tex]B = 0.120m/s^4[/tex]
[tex]t = \frac{1.5m/s^3}{0.120m/s^4}[/tex]
[tex]t = \frac{1.5}{0.120}s[/tex]
[tex]t = 12.5s[/tex]
Substitute [tex]t = 12.5s[/tex] in v(t) to get the maximum velocity
[tex]v(t) = \frac{At^2}{2} -\frac{Bt^3}{3}[/tex]
[tex]v(t) = \frac{A*12.5^2}{2} -\frac{B*12.5^3}{3}[/tex]
[tex]v(t) = \frac{156.25A}{2} -\frac{1953.125B}{3}[/tex]
Substitute: [tex]A = 1.5m/s^3[/tex] and [tex]B = 0.120m/s^4[/tex]
[tex]vmax = (156.25*1.5)/2 -(1953.125*0.120)/3[/tex]
[tex]v_{max} = 117.1875 - 78.125[/tex]
[tex]v_{max} = 39.0625[/tex]
The tides are considered an example of shallow-water waves because the tidal bulges have a wavelength that is on the order of __________.
The tides are considered an example of shallow-water waves because the tidal bulges have a wavelength that is on the order of thousands of kilometers.
Which of the aforementioned tide-related claims is true?Complete Response.The tides are caused by the sun and moon's tremendous gravitational pulls on the surface of the planet, which is the right answer.
Which of the following is untrue regarding tides' fundamentals?Response and Justification:Tides are not primarily caused by the gravitational influence of the sun, as is commonly believed.In reality, the Moon's gravitational pull is what mostly causes tides.
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According to the law of reflection, what is the relationship between the angle of incidence and the angle of reflection
The law of reflection, The relationship between the angle of incidence and the angle of reflection is that they are equal.
The angle of incidence is the angle between the incoming light ray and the normal line (a line perpendicular to the surface of the reflecting material), and the angle of reflection is the angle between the reflected light ray and the normal line. When a light ray strikes a reflection surface at a certain angle, it will be reflected back at the same angle. This relationship is represented by the equation.
=> angle of incidence = angle of reflection
This relationship holds true for all types of electromagnetic waves and for all surfaces that are reflective, whether they are smooth or rough, opaque or transparent. It's important to note that this is true for regular reflection, which is defined as the reflection of light off a smooth surface. If the surface is rough, the light rays are reflected in many different directions, this is called diffuse reflection.
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can someone please help me with this i really need this right now thank u ❤️
Answer:
1.constant acceleration.
2.0 ms
3. 0 ms
Explanation:
1. (D) uniformly accelerated motion
2. (A) zero
3. (B) -10 m/s
4. (C) -9.8 m/s^2
5. (B) projectile motion
A myopic person sees that her eyeglasses perscription is -4.00 D, for eyeglasses positioned 1.75 cm from her eyes. What is her far point?
After solving the problem the person's far point is 25 cm
What is myopic person?
A myopic person is someone who is near sighted and is unable to clearly see objects that are far away. This is caused by the eyeball being too long and the cornea having too much curvature. Light entering the eye is focused in front of the retina rather than directly on it, resulting in blurred vision for distant objects. Myopia is a common eye condition and can usually be corrected with glasses or contact lenses. In more severe cases, laser surgery may be necessary. People with myopia may need to wear their glasses or contact lenses all the time in order to see clearly, but they may be able to take them off when they are close to something they want to see clearly.
The far point is the farthest distance at which a person can see clearly without any corrective lenses.
The formula for calculating far point is 1/f = 1/d + 1/p, where f is the far point, d is the distance from the eye to the lens (1.75 cm in this case), and p is the power of the lens (in diopters) which is -4.00 D.
Plugging the values into the formula yields 1/f = 1/1.75 + 1/-4.00, which simplifies to 1/f = 4.00 - 0.5714. Solving for f gives f = 0.2500, or 25 cm.
Therefore, the person's far point is 25 cm.
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Two cells each of EMF 1.5 v and an internal resistance of 2 ohms are connected in parallel. calculate the current flowing when the cells are connected to 1 ohm resistor
Answer:2.30
Explanation:
10 points!
Which measuring tool should be used to measure the length of a marble track?
graduated cylinder
spring scale
metric ruler
stopwatch
Answer:
metric ruler
Explanation:
it counts legnth
A car travels at a constant speed around a circular track whose radius is 3.0 km. The car goes once around the track in 320 s. What is the magnitude of the centripetal acceleration of the car
The magnitude of the centripetal acceleration of the car is 0.0034 km/sec².
What is centripetal acceleration?Centripetal acceleration is the acceleration of an object moving in a circular path. It is directed towards the center of the circle and is responsible for the change in direction of the object's velocity.
The magnitude of the centripetal acceleration of an object moving in a circle is given by the formula:
a = v² / r
where a is the centripetal acceleration, v is the velocity of the object, and r is the radius of the circle.
Given that the car goes once around the track in 320 s, we can calculate its velocity by using the formula:
v = d / t
where d is the distance traveled and t is the time.
d = 2pir = 2pi3.0 km = 18.849 km
t = 320 sec
so the velocity of the car is v = 18.849 km / 320 sec = 0.059 km/sec.
We can now use the formula to find the centripetal acceleration of the car
a = v² / r = (0.059 km/sec)²/ 3.0 km = 0.0034 km/sec²
Hence, the magnitude of the centripetal acceleration of the car is 0.0034 km/sec².
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600 Joules of work is used to lift a box from the ground to a height of six meters. How much work would have been done if a lever would have been used with an effort arm of 12 meters and a load arm of 6 meters? (10 points)
a. 72 J
b. 100 J
c. 50 J
d. 600 J
Answer:
d. 600 J
Explanation:
You want to know the work done to lift a box using a lever with a mechanical advantage of 2, if the work required without the lever is 600 J.
LeverA lever trades force for distance. That is raising the box a distance of 6 m requires moving the lever arm a distance of 12 m, but only half the force is required. The product of force and distance is the same.
The total required work is unchanged: 600 J.
__
Additional comment
Actually, more work is required to lift the box using the lever. There is work applied to the box, and there is more work applied to moving the lever. (We have to assume a massless lever with no friction in these problems.)