2. The moon was not a graceful orb but a misshapen circle. No stars were visible. It spooked
Heidi that the moon was so clear and the stars so missing. Even as she looked out, the sky
around the moon darkened threateningly. It did not seem cold enough for snow. They would
have one of those grim, depressing, icy rains.
The sky was _____
A) mysterious
B) sparkling
C) smoky
D) peaceful

The average velocity is given by

Where d is the distance covered and t is the time taken.

For the given case, we have

d = 75 m

t = 8.9 s

Therefore, the average speed of the hockey player is 8.43 m/s

The hockey player is moving at a speed of 9.5 m/s.

Answer:

lubricant (decrease friction).

control production speed.

use only when required.

Answer:40N

Explanation:

Answer:

I guess rinse it out and wipe it up. It's not a hazardous substance so there's nothing to worry about.

These substances should be cleaned up rinsing the area or removing the compounds with a cloth and dispose of it in the trash.

Sugar is a chemical compound also called sucrose. Its chemical formula is C12H22O11. This compound is normally used to sweeten foods.

On the other hand, common salt is a chemical compound. Its chemical formula is NaCl. This compound is normally used to give food a salty taste.

According to the above, in which a student spilled some salt and sugar in the sink and does not know how to clean it, it can be concluded that the proper way to clean these chemical compounds is by rinsing the area or removing the compounds with a cloth and dispose of it in the trash because neither of them represents biological, chemical or physical risks and a specialized treatment is not required for them.

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Answer:4

Explanation:

Answer:12

Explanation:

Answer: A rotating body or system can be in equilibrium if its rate of rotation is constant and remains unchanged by the forces acting on it.

hope this helped

The angle of internal reflection can be found by using Snell's Law, which relates the angles of incidence and refraction for a given material. In this case, the index of refraction of the unknown liquid is known, which allows us to calculate the angle of refraction. The formula for Snell's Law is: n1sin(theta1) = n2sin(theta2), where n1 and n2 are the indices of refraction of the two materials and theta1 and theta2 are the angles of incidence and refraction, respectively.

Using the given values, we can calculate the angle of refraction to be 8.95 degrees. To find the angle of internal reflection, we can use the fact that the angle of incidence and the angle of reflection are equal, so the angle of internal reflection is also 13.0 degrees.
In summary, the angle of internal reflection for a ray of light originating inside a tank of unknown liquid with an index of refraction of 1.38 and an angle of incidence of 13.0 degrees is 13.0 degrees.

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Answer:

ADD ALL THEM AND ANSER WILL BE THERE 19.O

Explanatio

i. The work done by the load is load x distance moved by load.

ii. The work done by effort is effort applied x distance moved by effort.

iii. The mechanical advantage of the simple machine is Load/effort.

iv. The velocity ratio of the simple machine is 2.

v. The efficiency of the machine is M.A/V.R x 100%.

The work done by the load is the product of the load and the distance through which the load is moved. The magnitude is calculated as follows;

Work done by the load = load x distance moved by load

The work done by the effort is the product of the effort and the distance through which the effort is applied. The magnitude is calculated as follows;

Work done by effort = effort applied x distance moved by effort

M.A = Load/Effort

V.R = distance moved by effort / distance moved by load

V.R  = 30 cm/15 cm

V.R = 2

E = (M.A/V.R) x 100%

Thus, the work done by the load is load x distance moved by load.

The work done by effort is effort applied x distance moved by effort.

The mechanical advantage of the simple machine is Load/effort.

The velocity ratio of the simple machine is 2.

The efficiency of the machine is M.A/V.R x 100%.

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The minimum separation between the alpha particles is \(1.15 \times10^{-14} m\), when they approach each other without any deflection.

Given information:

Two alpha particles are separated by an enormous distance and each has an initial speed of \(3.0 \times106 m/s\).

We are to calculate their minimum separation, assuming no deflection from their original path and K.E.

Initial Kinetic Energy of alpha particle = \(K= \frac{1}{2}mv^2\)

Here, mass of alpha particle, \(m = 6.64 \times10^{-27} kg\)

Initial speed, \(v = 3.0 \times106 m/s\\\)

Substituting the given values, we get,

\(k=\frac{1}{2}\times 6.64\times10^{-27}\times(3.0 \times10^6)2\)

\(K = 2.988 \times 10^{-12} J\)

We know that, potential energy is defined as the energy possessed by a particle by virtue of its position relative to others.

When two alpha particles approach each other, their kinetic energy is converted into potential energy.

Minimum Separation,

\(d = \frac{(Q1.Q2)}{4\pi \varepsilon0K }\)

where, Q1 and Q2 are the charges on alpha particles and ε0 is the permittivity of free space.

The charges on alpha particles are equal and opposite in nature and given as,

\(Q1 = - Q2 \\Q1 = 2 \times1.6 \times10^{-19} C\)

Now, substituting the values in the formula, we get,

\(d=\frac{(2 \times1.6 \times10^{-19} \times2 \times1.6 \times10^{-19})}{(4\pi \times8.85 \times10^{-12} \times2.988 \times10^{-12})}\)

\(d = 1.15 \times 10^{-14} m\)

Therefore, the minimum separation between the alpha particles is \(1.15 \times10^{-14} m\), when they approach each other without any deflection.

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9.8 J of work done is required to launch the item (Option C).

To determine the work done in launching the object, we can use the formula:

Work = Force x Distance x Cos(theta)

where theta is the angle between the force vector and the direction of motion. In this case,

since the force is applied in the same direction as the motion of the object, theta is 0 degrees, and cos(theta) is 1.

Substituting the given values, we get:

Work = 19.6 N x 0.50 m x 1 = 9.8 J

Therefore, the work done in launching the object is 9.8 J (Option C).

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Complete question:

Question asked: how much work is done in launching the object?

Information in the passage included: 1.00 kg object initially at rest. The student applies a force of 19.6 N through a distance of .50 m to propel the object straight upward.

Answer:

The starting position of the runner.

Explanation:

When you look at the graph, you can see that the first point on the graph is twenty on the y-axis.

The runner starts at twenty, and ends at thirty.

Therefore, the runner starts at twenty on the y-axis, so it's the starting position of the runner.

The y-intercept tell you about the starting position of the runner.

The intersection of the graph of the function with the y-axis gives y-intercept of that function. The y-intercept is the value of y on the y-axis at which the considered function intersects it.

Assume that we've got: y = f(x)

At y-axis, we've got x = 0, so putting it will give us the y-intercept.

Thus, y-intercept of y = f(x) is y = f(0)

When we look at the graph, we can see that the first point on the graph is twenty on the y-axis.

The runner starts at twenty and ends at thirty.

Thus, the runner starts at twenty on the y-axis, so it is the starting position of the runner.

The y-intercept tell you about the starting position of the runner.

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The force F1 is equal and opposite to the downward force thus, F1 is equal to 60 N. The force F2 is inclined to 30 ° from leftward force and it is equal to 38.97 N in magnitude.

Force is an external agent acting on a body to deform it or to change its state of motion or rest. Force is a vector quantity and it is characterised by its magnitude and direction.

If two forces acting on a body from the same directions, then the net force will be the sum of these two forces. If they are acting from opposite directions, they will cancel each other in magnitude.

The force F1 is equal and opposite to the force acting downward. Thus its magnitude is 60 N. The force F2 is inclined to 30 ° from horizontal direction.

F2 = 45 cos 30 = 38.9 N.

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Answer:

Power is calculated by multiplying voltage by current.

Explanation:

If you're calculating the power of an athlete who is lifting weights,

or the power of a windmill that is pumping water from a well, or

the power of two horses turning millstones, then those electrical

units won't help at all.

But if you happen to be calculating the power delivered to an

electrical circuit or dissipated by an electrical device, then you

can use ...

               (voltage) times (current)

or

               (voltage)² divided by (resistance)

or

               (current)² times (resistance) .

The choice just depends on which quantities you know

or can easily measure.  

The test statistic (Z-score) is approximately 4.95.

To calculate the test statistic (Z-score) for this hypothesis test, we can use the formula:

Z = (sample mean - hypothesized population mean) / (standard deviation / sqrt(sample size))

Sample mean (X-bar) = 37

Hypothesized population mean (μ) = 30

Standard deviation (σ) = 8

Sample size (n) = 50

Substituting these values into the formula, we get:

Z = (37 - 30) / (8 / sqrt(50))

Z = 7 / (8 / 7.071)

Z = 7 / 1.414

Z = 4.95 (rounded to two decimal places)

A statistical hypothesis test is a technique for determining if the available data are sufficient to support a certain hypothesis. We can make probabilistic claims regarding population parameters using hypothesis testing.

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Answer:

0

Explanation:

When water is pumped out of well A, it causes a drop of 7 inches at point C; if water is pumped from well B into well A (at the same rate the water is pumped out of well A), then it will give a rise of 7 inches at well C. Therefore the net drawdown at well C is:

S = 7-7 = 0

The third statement (Magnetic forces can raise the trains off the track, reducing frictional forces acting against the train. Less work is needed to propel the train) describes how magnetic forces can be harnessed to increase the speeds at which trains travel.

The scientifically-recognized concept dubbed "magnetic force" dictates that there either exists attractive or repulsive forces created between opposing magnet poles and electrically-charged moving particles--thanks to electromagnetic activity taking place behind-the-scenes. Most notably, all magnets produce an invisible magnetic field with intensified strength around their polar regions.

If two standalone magnets confront one another with opposing polarities visible on either end, then an intrinsic attraction manifests itself due to their respective concentrated fields at those points; though if you flip both magnets around so that their identical polarity ends face each other instead, then repulsion happens thanks to stronger opposing fields.

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Answer:  \(135.48\ m/s^2\) ,\(13.82g\)

Explanation:

Given

Missile velocity raises from 0 to \(8.4\ km/s\)

Time taken \(t=62\ s\)

Convert velocity into m/s

\(\Rightarrow 8.4=8.4\times 1000=8400\ m/s\)

Acceleration is the change of velocity w.r.t time

\(\Rightarrow a=\dfrac{8400-0}{62}\\\\\Rightarrow a=135.48\ m/s^2\)

In terms of gravity, it is

\(\Rightarrow \dfrac{135.483}{9.8}=13.82\)

Therefore, acceleration in terms of g is \(13.82g\)

Electromagnet is the temporary magnet.

The strength of the magnetic field is directly related to the amount of current available. This means, the more coils, the more current, and the more opportunity for the electric charge to produce magnetism. Each turn of the wire in the coil has its own magnetic field.

Adding more turns to the coil of wire increases the strength of the field. Increasing the amount of current flowing through the coil also increases the strength of the magnetic field.

An electromagnet is a “temporary magnet,” which is created when an electric current passes through a coil, producing a magnetic field. Electromagnets can be powered by a variety of energy sources and are found in motors, cell phones, computers, clocks, and used in countless other technologies.

In our electromagnet, the battery is the energy source. As the battery’s current flows through the coil of wire it produces a magnetic field! The electricity flowing through the coil arranges the molecules in the nail so they attracted to certain metals. This magnetic attraction is what allows your electromagnet to pick up the paper clips.

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The amplitude of the resulting motion of the box is approximately 0.267 meters. To find the period of the resulting motion of the box after the stone is plucked vertically out of the box, we can use the formula for the period of a mass-spring system:

T = 2π√(m/k)

where T is the period, m is the mass attached to the spring, and k is the force constant of the spring.

In this case, the mass attached to the spring is the combined mass of the box and the stone, which is 5.50 kg + 3.44 kg = 8.94 kg. The force constant of the spring is given as 390 N/m.

Plugging these values into the formula, we have:

T = 2π√(8.94 kg / 390 N/m)

≈ 2π√(0.0229 kg/m)

≈ 2π(0.151 m)

≈ 0.951 s

So the period of the resulting motion of the box is approximately 0.951 seconds.

To find the amplitude of the resulting motion of the box, we can use the conservation of energy principle. When the stone is plucked out of the box, the total energy of the system is conserved.

The total energy of the system is given by the sum of the potential energy stored in the spring and the kinetic energy of the box:

E = (1/2)kx^2 + (1/2)mv^2

where E is the total energy, k is the force constant of the spring, x is the amplitude of motion, m is the mass of the box, and v is the velocity of the box at maximum speed.

Since the stone is plucked vertically out of the box without touching it, the velocity of the box at maximum speed is equal to the velocity of the stone just before it was plucked out.

Using the equation for the velocity of an object in simple harmonic motion, v = ωx, where ω is the angular frequency (ω = 2π/T), we can express the velocity in terms of the amplitude:

v = ωx = (2π/T)x = (2π/0.951 s)(0.075 m) ≈ 0.495 m/s

Plugging the values into the energy conservation equation:

E = (1/2)kx^2 + (1/2)mv^2

= (1/2)(390 N/m)(0.075 m)^2 + (1/2)(5.50 kg)(0.495 m/s)^2

≈ 5.515 J

Since the total energy is conserved, at any point in the motion, the total energy is equal to this value.

At the maximum displacement (amplitude) of the resulting motion, all of the energy is in the form of potential energy stored in the spring. Therefore, the amplitude can be found by setting the potential energy equal to the total energy and solving for x:

(1/2)kx^2 = 5.515 J

x^2 = (2 × 5.515 J) / (390 N/m)

≈ 0.0711 m^2

Taking the square root, we find:

x ≈ √(0.0711 m^2)

≈ 0.267 m

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According to the given statement The cars have the same speed but not the same velocity.

The electrical current generated by the gear's motion is directly inversely proportional to the gear's rate of rotation. The current is processed by a computer chip, which converts it into a number that represents your speed in either miles per hour or kilometres per hour.

The speedometer needle is turned by the magnet, which spins with the shaft, drawing a metal drum to it with the help of a hair spring. To provide a reading of the road speed, the needle rotates around the dial until the hair spring's restraint force causes it to come to rest.

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The purpose of nucleophilic substitution reactions of alkyl halides experiment is to demonstrate in the laboratory setting Nucleophilic substitution reactions of alkyl halides.

In this it is been  aimed to observe nucleophilic substitution reactions, SN1 and SN2 will by the addition of a solvent to mixtures of alkyl halides. In order to make this experiment effective a standard procedure is being used  and noted observations while each reaction occurred.

Nucleophilic substitution reactions are an important class of reactions that allow the interconversion of functional groups. For alcohols, the range of substitution reactions possible can be increased by utilizing the tosylates (R-OTs), an alternative method of converting the -OH to a better leaving group.

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When you increase the voltage in a beam, the radius of the beam changes in two ways beam divergence, beam elongation . This occurs because the voltage causes an increase in the kinetic energy of the electrons within the beam, which then leads to an increase in the velocity of the electrons.

The faster-moving electrons then begin to interact with each other, which causes the beam to spread out and elongate. On the other hand, when you increase the current in a beam, the radius of the beam changes in a different way. As the current increases, the radius of the beam becomes narrower, which is known as beam focusing.

This happens because the increased current leads to a stronger magnetic field, which then forces the electrons within the beam to move in a more focused and concentrated way. This process is called Lorentz force, and it causes the electrons to be pushed towards the center of the beam, thus making the beam more focused and narrower.

In summary, increasing the voltage causes beam divergence and elongation, while increasing the current leads to beam focusing and narrowing. These changes occur because of the interplay between the kinetic energy of the electrons, the magnetic field, and the interactions between the electrons themselves.

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Sure, I'd be happy to help you with that! Here are the answers to your questions:

(a) The potential energy of the shot as it left the hand relative to the ground can be calculated using the formula PE = mgh, where m is the mass of the shot (5.00 kg), g is the acceleration due to gravity (9.81 m/s^2), and h is the initial height of the shot (3.00 m). Therefore, PE = (5.00 kg)(9.81 m/s^2)(3.00 m) = 147.15 J.

(b) The kinetic energy of the shot as it left the hand can be calculated using the formula KE = 1/2mv^2, where m is the mass of the shot (5.00 kg) and v is the velocity of the shot (15.0 m/s). Therefore, KE = 1/2(5.00 kg)(15.0 m/s)^2 = 562.50 J.

(c) The total energy of the shot as it left the hand is simply the sum of the potential and kinetic energies, or TE = PE + KE = 147.15 J + 562.50 J = 709.65 J.

(d) At its maximum height, the shot has only potential energy, since it has come to a stop and is not moving. Therefore, the total energy of the shot at its maximum height is equal to its potential energy, or TE = PE = (5.00 kg)(9.81 m/s^2)(14.5 m) = 713.03 J.

(e) The potential energy of the shot at its maximum height is given by the same formula as before, PE = mgh, where m is the mass of the shot (5.00 kg), g is the acceleration due to gravity (9.81 m/s^2), and h is the maximum height of the shot (14.5 m). Therefore, PE = (5.00 kg)(9.81 m/s^2)(14.5 m) = 713.03 J.

(f) At its maximum height, the shot has no kinetic energy, since it is not moving. Therefore, the kinetic energy of the shot at its maximum height is zero.

(g) Just before it strikes the ground, the shot has lost all of its potential energy and is back to its original height of 3.00 m. Therefore, the potential energy of the shot is zero. The kinetic energy of the shot just before it strikes the ground can be calculated using the formula KE = 1/2mv^2, where m is the mass of the shot (5.00 kg) and v is the velocity of the shot just before it hits the ground (which we can assume is the same as its initial velocity, since air resistance is negligible). Therefore, KE = 1/2(5.00 kg)(15.0 m/s)^2 = 562.50 J.
(a) The potential energy (PE) of the shot as it left the hand relative to the ground can be calculated using the formula: PE = mgh, where m = 5.00 kg (mass), g = 9.81 m/s² (acceleration due to gravity), and h = 3.00 m (height). So, PE = 5.00 kg × 9.81 m/s² × 3.00 m = 147.15 J (joules).

(b) The kinetic energy (KE) of the shot as it left the hand can be calculated using the formula: KE = 0.5mv², where m = 5.00 kg (mass) and v = 15.0 m/s (velocity). So, KE = 0.5 × 5.00 kg × (15.0 m/s)² = 562.5 J.

(c) The total energy of the shot as it left the hand is the sum of its potential and kinetic energy: Total Energy = PE + KE = 147.15 J + 562.5 J = 709.65 J.

(d) The total energy of the shot at its maximum height remains constant since air resistance is negligible. So, Total Energy = 709.65 J.

(e) The potential energy of the shot at its maximum height can be calculated using the formula: PE = mgh, where m = 5.00 kg (mass), g = 9.81 m/s² (acceleration due to gravity), and h = 14.5 m (height). So, PE = 5.00 kg × 9.81 m/s² × 14.5 m = 710.725 J.

(f) At its maximum height, the shot's vertical velocity is 0, so its kinetic energy at that point is also 0 J.

(g) The kinetic energy of the shot just as it struck the ground can be determined by the conservation of energy principle: Total Energy = PE_ground + KE_ground. Since Total Energy is constant (709.65 J) and PE_ground is 0 (it's at ground level), the KE_ground = Total Energy = 709.65 J.

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The original work in physics that eventually led to the development of the atomic bomb was done by a team of scientists, including Albert Einstein, Enrico Fermi, and Robert Oppenheimer, among others.

An atomic bomb is a powerful explosive device that uses nuclear reactions to release enormous amounts of energy in the form of a blast, heat, and radiation. It was first developed during World War II and has since been used in warfare and nuclear testing.

Nuclear fission is a nuclear reaction in which the nucleus of an atom is split into two or more smaller nuclei, releasing a large amount of energy in the process. This is how nuclear power plants generate electricity and how atomic bombs create their explosive force.

According to the given information:

The original work in physics that eventually led to the development of the atomic bomb was done by a team of scientists, including Albert Einstein, Enrico Fermi, and Robert Oppenheimer, among others. They were involved in the development of nuclear fission, which is the process of splitting an atom's nucleus into smaller fragments, releasing a large amount of energy. This discovery eventually led to the creation of the atomic bomb during the Manhattan Project in the 1940s. The research done by these scientists has had a profound impact on the world, both positively and negatively, and continues to shape our understanding of the universe today.

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If a sprinter reaches his top speed of 10.9 m/s in 2.84 s , his total time to cover a distance of 100 m is 10.59 sec

We know that,

a = u / t

s = ut + 1/2 a\(t^{2}\)

where,

s = Distance

u = Initial velocity

a = Acceleration

t = Time

Given that,

Top speed = 10.9 m / s

Time taken to reach top speed = 2.84 s

a = 10.9 / 2.84 = 3.83 m / \(s^{2}\)

During the time period of 2.84 s, the distance covered is ,

s = ( 0 * 2.84 ) + 1/2 ( 3.83 * \(2.84^{2}\) ) = (3.83 * 8.07) / 2

s = 15.44 m

Consider the sprinter maintains a constant acceleration after reaching his top speed.

The distance remaining in 100 m track = 100 - 15.44 = 84.56 m

Time taken to cover 84.56 m at 10.9 m / s with no acceleration is

84.56 = ( 10.9 * t ) + 1 / 2 ( 0 ) ( \(t^{2}\) )

t = 7.75 s

Total time taken = 7.75 + 2.84 = 10.59 s

Acceleration is the rate of change of velocity. It is represented as a. Its unit is m / \(s^{2}\)

Therefore, if a sprinter reaches his top speed of 10.9 m/s in 2.84 s , his total time to cover a distance of 100 m is 10.59 sec

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The amount of variation in the tilt of the earth's axis is due to the gravitational force of the Moon

According to the Law of Universal Gravitation force, a force that attracts one particle to another is directly proportional to the product of the two masses and inversely proportional to the square of their distance from one another.

The gravitational force is caused by the gravitational pull of two objects on one another is stronger the more mass they have and the closer they are to one another. The energy holding the gases inside the sun. the power behind a ball's descent after being thrown into the air. the force that makes an automobile coast downhill even when the gas is not depressed. the force behind a glass you dropped falling

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Answer:

no

Explanation:

it's a graph

Answer:

It specifically is not a element but it has plenty of elements in it

Explanation: