A workman with a mass of 70 kg is climbing a 4-meter ladder of mass 10 kg that is leaning against a frictionless wall. The ground has a coefficient of friction (u) of 0.55. The angle between the ladder and horizontal is 30°. How far up the ladder will the man climb before the ladder slips? The acceleration due to gravity is 9.8m/s^2

The child closer to the book must apply a force of 49.05 N to support the board.

To solve this problem, we will use the principle of torque balance. The torque is the product of the force and the perpendicular distance from the force to the point of rotation. In this case, the point of rotation is the midpoint of the board.

First, we need to find the weight of the board. The weight is the force of gravity acting on the board, which is given by:

weight = mass x gravitational acceleration

weight = 5.00 kg x 9.81 m/[tex]s^2[/tex]

weight = 49.05 N

Next, we need to find the weight of the book.

The weight of the book is:

weight book = mass book x gravitational acceleration

weight book = 1.00 kg x 9.81 m/[tex]s^2[/tex]

weight book = 9.81 N

We can now find the torque due to the weight of the board and the book. The torque is the weight multiplied by the distance from the midpoint of the board:

torque weight = (weight board + weight book) x 1.00 m

torque weight = (49.05 N + 9.81 N) x 1.00 m

torque weight = 58.86 N*m

To balance this torque, the child closer to the book must apply a force perpendicular to the board at a distance from the midpoint of the board. We can call this distance x. The force applied by the child is the unknown we want to find, so let's call it F.

The torque due to the child's force is:

torque child = F x x

The torque balance equation is:

torque weight = torque child

Substituting the values we have found, we get:

58.86 N*m = F x x

We know that x = 1.20 m, so we can solve for F:

F = 58.86 N*m / 1.20 m

F = 49.05 N

Therefore, the child closer to the book must apply a force of 49.05 N to support the board.

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Force acts on it and changes its speed to 25 m/s in 5 s, then the value of force will be 250N.

The interaction between two objects, which can accelerate an object's motion, is described by the physical quantity force. In the International System of Units (SI), the Newton (N) is its standard unit of measurement.

We can use Newton's second law of motion, which states that the force acting on an object is equal to the object's mass divided by its acceleration, to determine the force's value. In this instance, the box has a starting speed of 0 m/s and a final speed of 25 m/s, which it reaches in 5 seconds. As a result, the box accelerates to:

a = (v_f - v_i) /t

= (25 m/s - 0 m/s) / 5 s

= 5 m/s²

There is no force produced by friction because the box is on a smooth surface. As a result, the only force exerted on the box is the force applied (F). The value of F can now be determined using Newton's second law of motion:

F = m × a

= 50 kg × 5 m/s²

= 250 N

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Identification of compounds can benefit from density. It is also a useful feature since it connects (or acts as a conversion factor between) a substance's mass and volume. Volume and mass are extended (or extrinsic) qualities of matter that are quantity dependent.

The force of an air mass acting on the earth's surface is known as atmospheric pressure. Remember that wind currents are created when the densities of two separate air masses differ.

Our wind currents are driven by the atmospheric pressure density, and denser air exerts a higher pressure than less dense air. Compared to the cold and dry air, the warm and humid air is less dense. The less dense air will then float on top of the thicker air in certain regions.

Therefore, Warm air masses rise while cold air masses descend because they are less dense.

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For these paces, one hour is equivalent to 3.27 miles or 5.26 kilometers for women and 3.8 miles or 6.1 kilometers for males in terms of distance.

The ratio of the total distance travelled by the body to the amount of time it took to complete that distance can be used to calculate average speed.

Formula for the average speed of a moving object with a range of speeds. The minute the minutes cancel, giving us kilometres per hour, and the speed would be 6 kilometres per hour; it then asks us to compare.

A student's average speed while walking would be 9 km/h if they covered a distance of 3 km in 20 minutes.

Therefore, to convert it to kilometres per hour, we can do so by simply converting our minutes into hours and remembering that there are 60 minutes in an hour.

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Transient simulation is an analysis is where a parameter such as a voltage or current is plotted against time.

A time domain transient analysis is where a parameter such as a voltage or current is plotted against time. If you are looking at an output you can see the behavior over a specified length of time. For this example we are going simulate the output of a half-wave rectifier.

In a transient simulation, you're looking at how a circuit reacts to a change in its inputs, and how the output eventually transitions between two states. These transitions between output states are not instant, and many applications require a smooth transient response between two states.

Transient analysis allows you to extract the decay constant and the natural resonance frequency from a graph of current or voltage in the time domain. The same idea applies any linear time invariant circuit driven with an arbitrary waveform. These driving sources do not need to be periodic in time.

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[tex]56497.1Nm^2[/tex] is the electric flux through one side of a cube that has a single point charge of placed at its center.

Electric flux is a measure of the electric field lines that are crossing the surface in electromagnetism. Although an electric field cannot flow on its own, it can be used to describe the strength of the field at any distance from the charge that generated it.

We may determine the electric flux across the cube's surfaces using Gauss's Law, then divide the result by 6.

We may eliminate the intermediary for Gauss's Law by using symmetry.

E * A = Qencl / ∈

where  [tex]= 8.85*10^{-12}[/tex]

The charge is [tex]-3.00*10^{-6} C[/tex]

Divide [tex]-3.00*10^{-6} C/ 8.85*10^{-12}[/tex] F/m

We obtain a flux of [tex]338983.0508 Nm^2[/tex] as a result.

We may calculate the flux through one side by dividing by 6:

[tex]338983/6 = 56497.1Nm^2[/tex]

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Correct question:

What is the electric flux through one side of a cube that has a single point charge of -3.00 µc placed at its center?

Given voltage drop across

EDLED is 1.8V in forward bias.

1.8 1.8 1.8

100

if

3.1kn

Applying Kirchhoff's voltage law to the circuit,

we get 10-1.8-1.8-1.8 - EXLOUD

<= 0=)46= 8×1000 [= 4.6 MA.

It is safe current level for a LED-for typical Current is arand power LED maximum forward 20 mA.

Voltage is the pressure from an electrical circuit's power source that pushes charged electrons (current) through a conducting loop, enabling them to do work such as illuminating a light. In brief, voltage = pressure, and it is measured in volts (V).

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In order to prepare for weightlessness, astronauts fly rollercoaster-style aircraft that are part of NASA's Reduced Gravity Program.

What is the gravity law?

Almost everything that has a mass in the universe is subject to the law of gravity. Like any two galaxies, any two objects will gravitate toward one another. Nevertheless, when the range is great enough, the attractions might occasionally become very modest or even zero. Its significance can be inferred from how all sorts of matter interact.

What does Earth's gravity on average weigh?

gravitation on Earth. The gravitational attraction that emerges from Newton's universal gravitational law and the centrifugal force that results from choosing an earthbound, spinning frame of reference combine to form the gravitational pull on Earth. The least powerful force is gravity.

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Answer:

When electric current passes through the tungsten filament, it gets heated up and starts to glow at a temperature around 2500 degree Celsius. If we do not fill any gas, at vacuum condition, the filament will evaporate due to high temperature. To protect the filament from damage, we are filling the bulb with inert gas.

Explanation:

i hope its help :)

The mass of [tex]Fe[/tex] is 24.56g and [tex]CO2[/tex] is 726.165g could be formed by the reaction of 0.22 mol of [tex]Fe2O3[/tex] with 5.5 mol of [tex]CO[/tex].

Given the number of moles of [tex]Fe2O3[/tex] is = 0.22mol

The number of moles of [tex]CO[/tex] = 5.5mol

The reaction of given compounds Fe2O3 and CO is described as below:

[tex]Fe2O3 + 3CO --- > 2Fe + 3CO2[/tex]

Here, we can see that 1 mole 0f [tex]Fe2O3[/tex] and 3 moles of [tex]CO[/tex] produce 3moles of [tex]CO2[/tex].

As given [tex]Fe2O3[/tex] acts as the limiting reagent such that:

Moles of [tex]Fe[/tex] produced = 0.22 mol x (2 mol [tex]Fe[/tex] / 1 mol [tex]Fe2O3[/tex]) = 0.44 mol Fe

Moles of [tex]CO2[/tex] produced = 5.5 mol [tex]CO[/tex] x (3 mol [tex]CO2[/tex]₂ / 1 mol [tex]CO[/tex]) = 16.5 mol

We know the molar mass of compound [tex]CO2[/tex] is and [tex]Fe[/tex] is then,

mass of [tex]Fe[/tex] used = moles x molar mass of [tex]Fe[/tex] = 0.44 x 55.84 = 24.56g

mass of [tex]CO2[/tex] used = moles x molar mass  = 16.5 x 44.01 = 726.165g

Hence, 24.56g of [tex]Fe[/tex] and 726.165g of [tex]CO2[/tex] are used in the reaction.

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The physical rules that govern the universe also govern our planet. However, the truth is that while physical rules may not alter, the constants and variables we use to approximation the properties of distant planets or solar bodies do.

Even though every solar body has unique characteristics, governing physical rules remain constant. However, in the present day, our experts have discovered a variety of outside bodies that defy fundamental rules and principles. It is not necessary for every object in the cosmos to behave according to the same physical principles because everything depends on time and space. With time and distance, they might change. As of right now, Newton, Kepler, and Einstein's fundamental physical principles all hold true; otherwise, they would all be in violation.

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Answer:

If this is the question : boy weighing 50kg climbs up a vertical height of 100m. Calculate the amount of work done by him. How much potential energy does he gain (g=9.8m/s2)

So the answer will be:

mass of boy = m = 50 kg   
height = h = 100m  

 since boy does not move anything with his force, work done by him is zero    work done on the boy = gain in potential energy   
 P.E=mgh    P.E=50×9.8×100   P.E=49KJ  so, potential energy gained by boy is 49 KJ 

Explanation:

The speed of the bat, in meters per second of vbat Is 2.68m/s.

The apparent frequency, I of the Reflected Pulse is.

f = v_s  + v_b / v_s  - v_b.f_0

∴ 45710 = 343 + v_b /  343 - v_b.(45000)

   45710 / 45000 = 343 + v_b /  343 - v_b

                             = 1.01578

343 + v_b = (1.01578) (343 - v_b)

v_b + (1.01578)v_b = 348.41 - 343

v_b(1 + 1.01578) = 5.41

v_b = 5.41 /(1 + 1.10578) = 5.41 / 2.01578

v_b = 2.68 m/s

Apparent frequency refers to the frequency of a wave as it appears to an observer who is in motion relative to the source of the wave. When an observer is moving towards a sound source, for instance, the frequency of the sound waves appears to be higher, resulting in a higher pitch. Conversely, when the observer is moving away from the source, the frequency appears to be lower, resulting in a lower pitch.

The Doppler effect is applicable to various types of waves, including sound waves, light waves, and electromagnetic waves. It has significant applications in fields such as astronomy, where it is used to measure the movement of celestial bodies, and in medical imaging, where it is used in ultrasound technology.

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Complete Question: -

A bat flying toward a wall emits a 45000-Hz sonar pulse. The pulse is reflected back from the wall and the bat hears the reflected pulse at a frequency of (45000 + 710) Hz. Take the speed of sound to be 343 m/s.

Find the speed of the bat, in meters per second.

vbat =

The muzzle velocity of the dart gun is 18.4 m/s. To solve this problem, we can use the equations of motion for projectile motion. We know that the dart travels a horizontal distance of 7.5 m and a vertical distance of 0.76 m.

We also know that the acceleration in the horizontal direction is zero, and the acceleration in the vertical direction is equal to the acceleration due to gravity, which is approximately 9.81 m/s^2. Let's first find the time it takes for the dart to travel 7.5 m horizontally. We can use the equation:

Distance = velocity x time

Rearranging this equation, we get: time = distance/velocity

Substituting the values we know, we get:

time = 7.5 m / velocity

Next, let's find the initial vertical velocity of the dart. We can use the equation: vertical distance = initial vertical velocity x time - 0.5 x acceleration x time^2

Since the dart is initially fired horizontally, its initial vertical velocity is zero. We can rearrange the above equation to solve for the initial velocity:m initial vertical velocity = vertical distance/time + 0.5 x acceleration x time

Substituting the values we know, we get: initial vertical velocity = 0.76 m / time + 0.5 x 9.81 m/s^2 x time; Now we can substitute the expression for the time we found earlier: initial vertical velocity = 0.76 m / (7.5 m / velocity) + 0.5 x 9.81 m/s^2 x (7.5 m / velocity)

Simplifying, we get:

initial vertical velocity = 0.10133 x velocity + 3.66375

Finally, we can use the Pythagorean theorem to find the muzzle velocity:

muzzle velocity = sqrt(velocity^2 + initial vertical velocity^2)

Substituting the expression we found for initial vertical velocity, we get:

muzzle velocity = sqrt(velocity^2 + (0.10133 x velocity + 3.66375)^2)

Using this method, I found that the muzzle velocity of the dart gun is approximately 18.4 m/s. Therefore, the answer to the problem is:

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In electromagnetic spectrum, the frequency and energy of electromagnetic waves increase.

The electromagnetic spectrum includes radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays. At the lowest end of the spectrum, radio waves have low frequency and low energy, while at the highest end, gamma rays have high frequency and high energy.

The relationship between frequency and energy can be described by the equation E = hf, where E is energy, h is Planck's constant, and f is frequency. As frequency increases, energy increases proportionally, and this relationship is consistent throughout the electromagnetic spectrum.

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According to the question, the distance between the particle and the cloth are: 2.7 m.

What is distance?

Distance is a numerical measurement of the amount of space between two points. It is usually measured in units such as meters, kilometers, feet, or miles. Distance can be used to measure the length of a path, the size of an area, or the length of a journey. Distance is also used to compare the size of two objects, such as the distance between two cities or the distance between two planets. Distance is an important concept in many fields, including mathematics, physics, engineering, geography, navigation, and astronomy.

The force between two charged particles can be calculated using Coulomb's Law, which states that the force between two charges is equal to the product of the charges divided by the square of the distance between them. In this case, we can rearrange the equation to solve for the distance between the two particles:

distance = (charge1 * charge2) / (force)

distance = (3.2 E−7 C * 6.7 E−7 C) / (4.8 E−4 N)

distance = 2.7 m

So, D is correct.

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Scientists can ascertain the isotope ratio and, consequently, the temperature at the time that layer was formed by examining the water molecules in each layer of ice.

With the aid of satellite, instrument, historical, and environmental records, scientists examine the Earth's climate and how it changes. Given that satellite and sensor lifespans have been relatively brief compared to Earth's life, using these data can be difficult.

Ice cores can help researchers reconstruct past greenhouse gas concentrations in the atmosphere, in addition to revealing past temperatures.

Therefore, The study of climatic evolution is known as climatology. This branch of science aids with people's comprehension of the atmospheric factors that influence weather patterns and temperature variations throughout time.

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Uniform electric field of magnitude [tex]1.81 * 10^5 N/C[/tex]pointing upward, away from the ground.

The small object is suspended motionless in a uniform electric field, which means that the electric force on the object is balanced by the force of gravity. We can use the equation for the electric force on a point charge in an electric field to find the magnitude of the electric field:

F = qE

where F is the electric force on the charge q, and E is the electric field. Since the object is motionless, the electric force on it must be equal and opposite to the gravitational force:

[tex]F_E = F_g[/tex]

qE = mg

m: mass of the object

g: acceleration due to gravity.

Substituting values:

E = [tex](mg) / q = [(2.6 g) * (9.8 m/s^2)] / (14 microC)[/tex]

μC: microcoulombs.

Use conversion factor:

[tex]1 microC = 10^(-6) C[/tex]

[tex]E = 1.81 * 10^5 N/C[/tex]

Electric field magnitude is [tex]1.81 * 10^5 N/C[/tex], and its direction is perpendicular to the ground, which is the direction of the force on the charge. The charge on the object is negative, so the direction of the electric field is opposite to the direction of the force on a positive charge. Therefore, the electric field points upward, away from the ground.

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An object of mass 0. 16kg is moving forwards at a speed of 0. 50m/s. A second object of mass 0. 10kg is at rest. 0.375 m/s is the speed of the first object after the collision.

Just apply momentum conservation since the net external force on the system is zero.

0.16 × 0.50 + 0.10 × 0 = 0.10 × 0.50 + 0.16 ×v

0.080 = 0.050 + 0.16v

0.16v = 0.030

v = 0.375 m/s

The initial velocity is the velocity of the item or system prior to the impact. In contrast, final velocity refers to the velocity of the item after the contact. Use the momentum equation p = m•v to compute the momentum or velocity of an item if given the other values. The answer is no for a single pair of equal mass items.

When two masses collide in a frame with their centers of mass at rest, each ball will leave with the same (or less) speed that it entered with.

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A system has an equal chance of being in any microstate that corresponds to its current macrostate. Equilibrium is defined as an isolated system that meets the postulate of equal a priori probabilities.

The probability of discovering a system in a specific microstate is simply one divided by the total number of microstates.
The thermodynamic probability (denoted by W) is equal to the number of microstates that realise a given macrostate, so W = 1.
To put it simply, the microcanonical ensemble is defined as assigning an equal probability to every microstate whose energy falls within a range centred on E. The probability of all other microstates is set to zero.

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The second clod of material, is more likely to form a solar system.

Gravity plays a crucial role in the formation of solar systems. When objects with large masses are closely packed together, their strong gravitational attraction can cause them to start rotating and clumping together into larger bodies. Over time, the largest of these bodies may become the central star of the solar system, while the smaller objects continue to orbit it. This process is known as accretion, and it is the first step in the formation of a solar system.

On the other hand, if the objects have small masses and are widely spaced, their gravitational attraction is too weak to cause them to clump together and form a central star. Instead, they would continue to float freely in space, never becoming dense enough to collapse under their own gravitational force.

In conclusion, it is the strong gravitational attraction between closely packed objects with large masses that makes it more likely for a clod of material to form a solar system.

This impact may have caused Mars' distinctive "two faces" — a high, cratered crust in the southern hemisphere and a smooth, low crust in the northern hemisphere. Thus, option B is correct.

The appearance of a bear's nose is produced by a collapse structure with a V shape. The circular fracture could be the result of a deposit collapsing on top of an impact crater that was buried and later filled with mud or lava.

It's possible that the protrusion resembles a nose is a volcanic or mud vent. Mars may contain the largest impact crater in the solar system, which is covered in lava.

Therefore, the face of a bear appears to be formed on the surface of Mars by a hill with a V-shaped collapse structure, two craters, and a circular fracture pattern, which may represent the remains of a buried impact crater.

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The time taken by hiker is L/60 minutes (L = length of trail)

However, we can show the steps to find the answer if we have the length of the trail.

Let's assume that the length of the hiking trail is L meters. To make a complete circuit around the trail, the hiker needs to cover a distance of 2L meters (going up and coming back down).

                                  time = distance / speed

                                  time = (2L meters) / (2 m/s) = L seconds

                                  time in minutes = L seconds / 60

If we knew the length of the trail in meters, we could calculate the time taken in minutes using this formula.

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Answer:

It is because of the gravity. Gravity pulls things down to an planet/star, but a space probe is far enough from the Earth, so it is pulled into the Earth's orbit.

The minimum distance the observer has to travel in the x-direction to hear the smallest possible sound intensity is half of this distance or 0.6 m.

In this scenario, the observer is located at the midpoint between the two loudspeakers, and the two loudspeakers are emitting sound waves with the same frequency and in phase. As a result, the sound waves from each speaker will interfere with each other constructively, creating a region of high sound intensity known as a sound interference pattern.

If the observer moves slightly in either direction along the x-axis, the path difference between the two sound waves will change, causing the interference pattern to shift. This shift will result in a change in the sound intensity heard by the observer.

To find the minimum distance the observer has to travel to hear the smallest possible sound intensity, we can use the concept of destructive interference. Destructive interference occurs when the path difference between the two sound waves is equal to an odd multiple of half the wavelength of the sound wave.

The wavelength of a sound wave with a frequency of 425 Hz can be calculated using the formula:

wavelength = speed of sound / frequency = 340 m/s ÷ 425 Hz = 0.8 m

If the observer moves a distance of x in the x-direction towards one speaker and away from the other, the path difference between the two sound waves will be:

path difference = distance traveled by a sound wave from one speaker - distance traveled by the sound wave from the other speaker

= (x + d/2) - (x - d/2)

= d

where d is the distance between the two speakers.

To create destructive interference, the path difference should be equal to an odd multiple of half the wavelength:

d = (2n+1) × wavelength / 2

where n is an integer.

Since we want to find the minimum distance x, we want to find the smallest value of n that satisfies this equation.

The smallest possible sound intensity occurs when the two sound waves interfere destructively, resulting in a sound wave with zero amplitude. Therefore, we want to find the value of n that corresponds to destructive interference.

For destructive interference, n must be an odd integer. The smallest odd integer that satisfies the above equation is n = 1. Substituting this value into the equation and solving for d, we get:

d = (2n+1) × wavelength / 2 = 3/2 × wavelength = 1.2 m

Therefore, the minimum distance the observer has to travel in the x-direction to hear the smallest possible sound intensity is half of this distance, or:

x = d / 2 = 0.6 m.

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a) The bolt 1.38 seconds to fall through the last 20% of its fall.

b) The bolt begins the last 20% of its fall 3.06 seconds after it is dropped.

c) The speed of the bolt just before it hits the ground is 42.43 m/s.

(a) The time it takes for the bolt to fall through the last 20% of its fall can be calculated using the kinematic equation:

[tex]y = vi*t + (1/2)at^2[/tex]

where y is the distance fallen, vi is the initial velocity (which is 0), a is the acceleration due to gravity ([tex]-9.8 m/s^2[/tex]), and t is the time taken.

Let's call the total distance fallen by the bolt "d". Then, the distance fallen in the last 20% of the fall is 0.2d, and the distance fallen before that is [tex]0.8d[/tex]. So we can write:

[tex]0.2d = (1/2)at^2[/tex]

Solving for t, we get:

[tex]t = sqrt((0.2d)/(0.5*a))[/tex]

Plugging in the values, we get:

[tex]t = sqrt((0.290)/(0.5(-9.8))) = 1.38 seconds[/tex]

To find the speed of the bolt at the end of this 20% fall, we can use the kinematic equation:

[tex]v = vi + a*t[/tex]

where v is the final velocity, vi is the initial velocity (which is 0), a is the acceleration due to gravity ([tex]-9.8 m/s^2[/tex]), and t is the time taken.

Plugging in the values, we get:

[tex]v = 0 + (-9.8)*1.38 = -13.524 m/s[/tex]

The negative sign indicates that the velocity is downward.

(b) The time at which the bolt begins the last 20% of its fall can be found by multiplying the total time taken to fall by 0.8 (since the first 80% of the fall takes 80% of the total time):

[tex]t_start = 0.8sqrt((2d)/g) = 0.8sqrt((2*90)/9.8) = 3.06 seconds[/tex]

(c) The speed of the bolt just before it hits the ground can be found using the kinematic equation:

[tex]v^2 = vi^2 + 2ay[/tex]

where v is the final velocity, vi is the initial velocity (which is 0), a is the acceleration due to gravity [tex](-9.8 m/s^2)[/tex], and y is the distance fallen.

Plugging in the values, we get:

[tex]v = sqrt(0 + 2*(-9.8)*90) = 42.43 m/s[/tex]

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