what is the coefficient of friction if the friction force is 77.4n and the normal reaction force is 120n

Answer: 1234 is correct

hope that helps

Explanation:

The figure skater increases the speed of her spin to 10 revolutions per second by drawing her arms inside.

The speed of the skater's spin drops by a factor of two as she spreads her arms out in front of her, doubling the moment of inertia. She dramatically reduces her inertia moment while folding her wrists in, resulting in a considerable increase in rotational velocity.

When does a speedskater reach a point of inertia?

During skating, the skater's mass is measured in terms of how far it extends from the axis around the direction that he or herself is spinning. This is known as the inertia moment, or moment of inertia The magnitude of its moment of inertia increases with distance from the axis. The force required to halt a moving item is measured by momentum.  

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Answer:

the correct answer is (c) -, -.

Explanation:

When an object is placed in front of a convex mirror at infinity, the image formed is a virtual image located at the focal point of the mirror.

According to the New Cartesian Sign Convention, the focal length of a convex mirror is negative. Therefore, the sign of the focal length in this case is "-".

Since the image is formed behind the mirror and is a virtual image, its distance from the mirror is negative. Therefore, the sign of the image distance in this case is also "-".

Therefore, the correct answer is (c) -, -.

The two masses have a ratio of mB/mA = IB/IA = 4. Mass A must be put at a distance of x = [mB R (2 + sqrt(3))] / 2 for IB to equal IA (mA - mB) are As a result, mass A must be positioned at a distance of x = [mB R (2 + (3))] / [mB R] for IB to equal IA (mA - mB).

The sum of each particle's product of mass and the square of its distance from the axis of rotation is what determines the moment of inertia. The moment of inertia formula is given as I = miri2.

The formula for the total moment of inertia about the axis of rotation is

I = IA + IB

If IB = 4IA, then:

I = IA + 4IA = 5IA

So, the ratio of the two masses is:

mB/ mA = IB/IA = 4

(b)Let x represent the separation between mass A and the rotational axis. Thus, mass A's moment of inertia is:

IA = mA x²

And with respect to the axis of rotation, the moment of inertia of mass B is:

IB = mB (R - x)²

If IB = IA, then:

mA x² = mB (R - x)²

Expanding the right-hand side and simplifying, we get:

mB x² - 2mB Rx + mB R² = mA x²

(mA - mB) x² + 2mB Rx - mB R² = 0

The solutions of this equation are:

x = [ -2mB R ± √((2mB R)² - 4(mA - mB)(-mB R²))] / 2(mA - mB)

Simplifying, we get:

x = [mB R (2 ± √(3))] / (mA - mB)

Since x must be positive, we take the solution with the plus sign:

x = [mB R (2 + √(3))] / (mA - mB)

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The minimum diameter at section (1) to avoid cavitation at that point is 5.057 cm (rounded to three decimal places).

To determine the minimum diameter at section (1) to avoid cavitation at that point, we can use the following formula:

d1 = √((4q)/((πv)),

where

q = the flow rate (m³/s)v = the velocity of water (m/s)

To avoid cavitation, the velocity of water at section (1) should not exceed the critical velocity, which can be calculated using the following formula:

vc = √((p2-pv)/(0.5*density)),

where

p2 = the pressure at section (2) (Pa)

pv = the vapor pressure of water at the maximum temperature (Pa)

density = the density of water (kg/m³)

Assuming that the pressure at section (2) is atmospheric (101325 Pa), the vapor pressure of water at 30°C is 4243.7 Pa.

Thus,

vc = √((101325-4243.7)/(0.5*1000)) = 14.697 m/s

To determine the flow rate, we can use the continuity equation:

q = ((π/4)d2²v

where d2 is given as 12 cm, or 0.12 m. If we assume that the flow is steady and incompressible, the flow rate is constant throughout the pipe.

Thus,

q = ((π/4)(0.12)²v

Combining these equations, we get:

d1 = √((4*((π/4)(0.12)²v)/((πvc))

d1 = √((0.0144v)/14.697)

d1 = 0.003762 × [tex]v^{0.5[/tex]

To avoid cavitation, d1 must be greater than or equal to the minimum diameter required at section (1). Therefore, we can set d1 equal to the critical diameter, which is given by:

dc = √((4q)/((πvc))

Substituting the values for q and vc, we get:

dc = √((π/4)(0.12)² 14.697)

dc = 0.05057 m

Therefore, the minimum diameter at section (1) to avoid cavitation at that point is 5.057 cm (rounded to three decimal places).

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The magnitude of the load on the crane before the collapse was 7871.48 N, which is well below the maximum load rating of 500 kg.To determine the load on the crane, we need to use the principles of static equilibrium.

The crane is in equilibrium when the sum of the forces acting on it is zero and the sum of the torques is also zero.The forces acting on the crane are tension in the cable and the weight of the horizontal beam. the torque is due to the weight of the horizontal beam.First, calculate the weight of the horizontal beam:

W = mgL = 85.105.0009.810 = 4168.52 N, where m is the mass per meter of length, g is the acceleration due to gravity, and L is the length of the beam.Now calculating the torque due to the weight of the beam :

τ = W*(h/2) = 4168.52*(2.250/2) = 4686.03 Nm, where h is the height of the horizontal beam. since the  crane is equilibrium, the tension in the cable must balance the weight of the beam which is  T = W. now  substituting the values we get :

=>12040 N = 4168.52 N + L=> 12040 N - 4168.52 N = 7871.48 N

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Cells represents the building blocks for all living things.

Cells are called "the building blocks of life" because they are the basic structural and functional elements of human life. Cells are the basic units of all stages of biological organization. This suggests that cells of different species create tissues, organs, and organ systems.

The cornerstone of all living beings is the cell. There are billions of cells in the human body, each serving a specific purpose.

Your DNA contains information that tells our cells how to make proteins. Vital bodily processes including digestion, cell growth and muscle movement are fueled by protein.

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Answer:

13 cm

Explanation:

13 cm is the image distance

The forces acting on a skateboard include gravity, friction, air resistance, and applied force, and they all affect the motion of the skateboard in different ways.

When a skateboard is in motion, several forces act on it that affect its movement. The main forces acting on a skateboard are:

Gravity: This is a force that pulls the skateboard downwards towards the ground. The weight of the skateboard and the rider are also affected by gravity.

Friction: This is a force that opposes the motion of the skateboard. Friction is caused by the skateboard's wheels rolling on the ground or surface, and it can slow down the skateboard's speed.

Air resistance: This is a force that opposes the motion of the skateboard as it moves through the air. The faster the skateboard moves, the more air resistance it experiences.

Applied force: This is the force applied by the rider to propel the skateboard forward or to perform tricks. The amount of applied force determines how fast or slow the skateboard moves.

The combination of these forces affects the motion of the skateboard. If the applied force is greater than the forces of friction, air resistance, and gravity, the skateboard will accelerate. If the forces of friction, air resistance, and gravity are greater than the applied force, the skateboard will slow down or come to a stop.

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The wavelength of the wave is 2.4 m, the frequency of the wave is 0.6593 Hz, and the speed of the wave is 0.2637 m/s.

A transverse wave is observed to be moving along a lengthy rope

Distance between adjacent crests (wavelength) = λ = 2.4 m

Number of crests passing a point = 6

Time taken for these crests to pass = t = 9.1 s

We can use the formula:

Speed = Distance / Time

Speed of the wave (v) = λ / t

Frequency of the wave (f) = Number of crests / Time taken

So, substituting the given values, we get:

Speed of the wave (v) = λ / t

v = 2.4 m / 9.1 s

v = 0.2637 m/s

Frequency of the wave (f) = Number of crests / Time taken

f = 6 / 9.1 s

f = 0.6593 Hz

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The fourth option best represents the proper graph, which resembles a branch of a hyperbola.

From Coulomb's Law.

F = k · (q₁ · q₂) / r²

where

Q1 and Q2 are the charges of the two particles, F is the electrostatic force separating them, k is the Coulomb's constant, and r is the separation between them.

The force becomes weaker as the two particles move apart.

Moreover, as r approaches zero, F approaches 1 / 0 =. F is endlessly powerful when there's no separation between the two particles. As a result, the force axis will never be touched by the force about distance graph.

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Answer:

a force

Explanation:

Answer: To compare the force of electrostatic repulsion and gravitational attraction between two alpha particles, we need to calculate both forces using the given information:

Electrostatic force of repulsion between two alpha particles:

Coulomb's law states that the force of electrostatic repulsion between two charged particles is given by:

F = (kq1q2)/r^2

where k is Coulomb's constant, q1 and q2 are the charges of the two particles, and r is the distance between them.

Here, q1 = q2 = 3.2×10^-19 C (charge of alpha particle), and r = distance between two alpha particles.

We know that two alpha particles are doubly ionized helium nuclei, so they each contain two protons. Thus, their separation distance will be approximately equal to the sum of their radii, which is about 4 fm (4 × 10^-15 m).

Plugging in these values, we get:

F_elec = (8.85×10^-12 * (3.2×10^-19)^2) / (4×10^-15)^2

F_elec = 8.17×10^-28 N

Gravitational force of attraction between two alpha particles:

The force of gravitational attraction between two particles is given by:

F = G*(m1*m2)/r^2

where G is the gravitational constant, m1 and m2 are the masses of the two particles, and r is the distance between them.

Here, m1 = m2 = 6.68×10^-27 kg (mass of alpha particle), and r = distance between two alpha particles.

Plugging in these values, we get:

F_grav = (6.67×10^-11 * (6.68×10^-27)^2) / (4×10^-15)^2

F_grav = 3.71×10^-57 N

Therefore, we can see that the force of electrostatic repulsion between two alpha particles is much greater than the force of gravitational attraction between them.

F_elec/F_grav = (8.17×10^-28 N) / (3.71×10^-57 N) ≈ 2.2×10^29

Explanation:

Answer: The electrostatic force of repulsion between the two alpha particles is about 5.5 × 10^48 times stronger than the gravitational force of attraction between them.

Explanation:

The force of electrostatic repulsion between two alpha particles can be calculated using Coulomb's law:

F_e = k * (q1 * q2) / r^2

where k is the Coulomb constant (1/4πε0), q1 and q2 are the charges of the particles (in coulombs), and r is the distance between them (in meters).

For alpha particles, the charge is 3.2 × 10^-19 C and the distance between them can be assumed to be the sum of their radii, which is approximately 2 x 10^-15 m. Using the given value of the Coulomb constant and the values for charge and distance, we can calculate the force of electrostatic repulsion:

F_e = (9 × 10^9 Nm²/C²) * [(3.2 × 10^-19 C)^2 / (2 × 10^-15 m)^2]

= 1.15 × 10^-28 N

The force of gravitational attraction between two alpha particles can be calculated using Newton's law of gravitation:

F_g = G * (m1 * m2) / r^2

where G is the gravitational constant (6.67×10^-11 Nm²/kg²), m1 and m2 are the masses of the particles (in kg), and r is the distance between them (in meters).

For alpha particles, the mass is 6.68 × 10^-27 kg, and the distance between them can be assumed to be the sum of their radii, which is approximately 2 x 10^-15 m. Using the given value of the gravitational constant and the values for mass and distance, we can calculate the force of gravitational attraction:

F_g = (6.67 × 10^-11 Nm²/kg²) * [(6.68 × 10^-27 kg)^2 / (2 × 10^-15 m)^2]

= 2.1 × 10^-77 N

Comparing the two forces, we see that the electrostatic force of repulsion is much stronger than the gravitational force of attraction:

F_e / F_g = (1.15 × 10^-28 N) / (2.1 × 10^-77 N) = 5.5 × 10^48

Therefore, the electrostatic force of repulsion between the two alpha particles is about 5.5 × 10^48 times stronger than the gravitational force of attraction between them.

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The kinetic energy before the collision is 358 J and the kinetic energy after the collision is 232 J.

KE_before = (1/2) * m1 * v1^2 + (1/2) * m2 * v2^2

KE_before = (1/2) * 8 * 4^2 + (1/2) * 3 * 14^2

= 64 + 294

= 358 J

m1 * v1 + m2 * v2 = m1 * v1' + m2 * v2'

Substituting the given values, we get:

8 * 4 + 3 * 14 = 8 * 2 + 3 * v2'

Solving for v2', we get:

v2' = (8 * 4 + 3 * 14 - 3 * v1') / 3

The negative sign indicates that the 3kg ball is moving in the opposite direction after the collision. We also know that the 8kg ball is moving away at 2m/s. Therefore,

v1' = 2 m/s

Substituting this value, we get:

v2' = (8 * 4 + 3 * 14 - 3 * 2) / 3

= 12 m/s

The kinetic energy after the collision is:

KE_after = (1/2) * m1 * v1'^2 + (1/2) * m2 * v2'^2

Substituting the given values, we get:

KE_after = (1/2) * 8 * 2^2 + (1/2) * 3 * 12^2

= 16 + 216

= 232 J

Kinetic energy is the energy an object possesses due to its motion. In physics, it is defined as the energy that an object possesses due to its motion, and it is dependent on the mass and velocity of the object. The formula for kinetic energy is KE = 1/2mv², where KE is the kinetic energy, m is the mass of the object, and v is the velocity of the object.

Kinetic energy is a scalar quantity, meaning that it has only magnitude and no direction. It is a fundamental concept in physics, and it is used to describe many phenomena, including the motion of particles, the motion of objects, and the conversion of energy between different forms. The kinetic energy of an object can be transformed into other forms of energy, such as potential energy or thermal energy, through various processes.

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The color of an object has to do with the light wavelength. A white t-shirt looks yellow because it absorbs all the colors while black white all the wavelengths of light. A ripe mango is yellow because reflect all the reflects wavelengths.

The light wavelength has an impact on an object's color of which the object reflects. Because it absorbs all hues, a white t-shirt seems yellow, but a black one emits all light wavelengths. A ripe mango appears yellow because, when white light strikes it, its atomic impurities bounce all the wavelengths of light at our sight more than the other colors. ​

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Answer:

The parallax method relies on measuring the apparent shift in position of a star against the background of more distant stars as the Earth orbits the Sun. The angle of this shift is called the parallax angle, and it can be used to calculate the distance to the star.

To determine the distance between the two stars in the problem, we need to use some trigonometry. Since the stars are 5 degrees apart in the night sky, we can use the formula:

distance = (angular separation / 2) x (1 / parallax)

Plugging in the values for the first star, we get:

distance1 = (5 / 2) x (1 / 0.11) = 22.7 light-years

And for the second star:

distance2 = (5 / 2) x (1 / 0.13) = 19.2 light-years

Now, we can use the Pythagorean theorem to find the distance between the two stars:

distance between stars = √(distance1^2 + distance2^2) = √(22.7^2 + 19.2^2) = 29.4 light-years

Therefore, the two stars are about 29.4 light-years apart from each other.

The distance between the boat and the camera is 0.0525 m. The boat must move closer by a distance of  35 mm to fill the width of the film.

you have a camera with a 35.0-mm-focal-length lens and 36.0-mm-wide film. you wish to take a picture of a 12.0-m-long sailboat but find that the image of the boat fills only the width of the film.

(a) Given data:

The focal length of the lens, f = 35.0 mm

Width of the film, w = 36.0 mm

Length of the sailboat, L = 12.0 m

Length of the image of the sailboat on film = Width of the film

Let the distance between the boat and the camera be x.

The object distance, u = ?

Image distance, v = f

Let M be the magnification of the image, then we have:

 M = v/u

Width of the image, W' = w

Since the image of the boat fills only half of the width of the film,

W' = w/2.

Now, using the relation,

1/f = 1/u + 1/v

Putting f = 35mm, v = 35mm, and solving for u, we get

u = 52.5 mm = 0.0525 m

Therefore, the distance between the boat and the camera is 0.0525 m.

(b)Width of the image, W = w = 36 mm

Width of the sailboat, L = 12 m

Let the new distance between the boat and the camera be y.

The new image distance, v' = f

We know that the magnification of the image is given by M = v'/u'.

And the width of the image of the boat is given by:

W = (M)(L)

Using the relation,

1/f = 1/u' + 1/v', we can find the object distance, u'.

Substituting the given values, we get

u' = 0.0175 m = 17.5 mm

Therefore, the boat must move closer by a distance of (52.5 - 17.5) mm = 35 mm to fill the width of the film.

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The voltage dropped across R₃ is 52.68 volts.

To determine the voltage dropped across R₃, we can use the voltage divider formula:

V₃ = ( R₃ / ( R₁ + R₂ + R₃ + R₄ ) ) x ET

Substituting the given values, it can be calculated as:

V₃ = (36 Ω / ( 15 Ω + 18 Ω + 36 Ω + 13 Ω ) ) x 120 V

V₃ = ( 36 Ω / 82 Ω ) x 120 V

V₃ = 52.68 V

Therefore, the voltage dropped across R₃ is approximately 52.68 volts.

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i. the period of oscillation: Speed, V=ωr2−y2.  ii. the acceleration at the maximum displacement: V=10π×(0.05)2−(0.03)2=10π×0.04=0.4π m/s.

iii. the velocity at the center of motion​: V=10π×(0.05)2−02

given = 5 cm = 0.05 m

T = 0.2 s

ω=2π/T=2π/0.2=10πrad/s

At the point when relocation is y, then acceleration, a=−ω2y

Speed, V=ωr2−y2

Case (a) When y=5cm=0.05m

a=−(10π)2×0.05=−5π2m/s2

V=10π×(0.05)2−(0.05)2=0

Case (b) When y=3cm=0.03m

a=−(10π)2×0.03=−3π2m/s2

V=10π×(0.05)2−(0.03)2=10π×0.04=0.4π m/s

Case (c) When y=0

a=−(10π)2×0=0

V=10π×(0.05)2−02

T = 2π√(m/k). By timing the length of one complete oscillation we can decide the period and thus the frequency. Note that on account of the pendulum, the period is free of the mass, while on account of the mass of spring, the period is free of the length of the spring.

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the complete question is:

A body moving in simple harmonic motion has an amplitude of 10cm and a frequency of 100 Hz. Find i. the period of oscillation, ii. the acceleration at the maximum displacement, iii. the velocity at the center of motion​.

The minimum power density measurable is 0.1 times the dark current density divided by the elementary charge and the external quantum efficiency of the detector.

The minimum power density measurable can be calculated using the following formula:

P = Jsc / (q * η)

where P is the power density, Jsc is the short-circuit current density, q is the elementary charge, and η is the external quantum efficiency of the detector.

Assuming that the photogenerated current is 10% of the dark current, the total current density (J) can be expressed as:

J = Jdark + Jph

where Jdark is the dark current density and Jph is the photogenerated current density.

Since Jph is 10% of Jdark, we can express Jph as:

Jph = 0.1 * Jdark

The short-circuit current density (Jsc) can be approximated as Jph because the detector is operated under short-circuit conditions.

Thus, Jsc ≈ Jph = 0.1 * Jdark

Substituting this into the formula for P, we get:

P = Jsc / (q * η) ≈ Jph / (q * η) = 0.1 * Jdark / (q * η)

Therefore, the minimum power density measurable is 0.1 times the dark current density divided by the elementary charge and the external quantum efficiency of the detector.

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Answer:

KE = 1/2 M V^2

V = (2 KE / M)^1/2 = (2 * 40 / .1)^1/2 = 28.3 m/s

Its average separation from of the Sun is 6.1 AU, or (225/3)AU.

When the period (P) is written in years and the orbital radius (a) is represented in light years away (1 AU is the arithmetic mean between the Sun and the planet Earth), Kepler's Third Law states that P2 = a3. where P is measured in Earth years, an is measured in astronomical units, and M is the centre object's mass expressed in Sun-mass units.

As seen from it above Middle Latitudes, the Earth circles the Sun at an arithmetic mean of 149.60 million kilometres (92.96 million miles), anticlockwise. One axial tilt year, or 365.249 days, is needed to complete one orbit, during which duration Earth has travelled 940 million kilometres (584 million mi).

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The mass of the bullet is approximately 0.21 kg (to 2 significant figures).

We can use the principle of conservation of momentum to solve this problem. The total amount of momentum prior to and following the impact are equal.

Let the mass of the bullet be "m" kg.

The momentum of the bullet before the collision is:

p1 = m × 50 m/s = 50m

The momentum of the bullet and block after the collision is:

p2 = (m + 0.5 kg) × 15 m/s = 15(m + 0.5)

According to the principle of conservation of momentum:

p1 = p2

50m = 15(m + 0.5)

50m = 15m + 7.5

35m = 7.5

m = 7.5/35 = 0.2143 kg (rounded to 2 significant figures)

Therefore, the mass of the bullet is approximately 0.21 kg (to 2 significant figures).

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1. The troposphere is the lowest layer of Earth's atmosphere. Most of the mass (about 75-80%) of the atmosphere is in the troposphere. Most types of clouds are found in the troposphere, and almost all weather occurs within this layer.

2. The stratosphere is very dry air and contains little water vapor. Because of this, few clouds are found in this layer and almost all clouds occur in the lower, more humid troposphere. Polar stratospheric clouds (PSCs) are the exception. PSCs appear in the lower stratosphere near the poles in winter.

3. The mesosphere lies between the thermosphere and the stratosphere. “Meso” means middle, and this is the highest layer of the atmosphere in which the gases are all mixed up rather than being layered by their mass. The mesosphere is 22 miles (35 kilometers) thick.

4. The thermosphere is a layer of Earth's atmosphere that is directly above the mesosphere and below the exosphere. It extends from about 90 km (56 miles) to between 500 and 1,000 km (311 to 621 miles) above our planet.

5. The ozone layer acts as a natural filter, absorbing most of the sun's burning ultraviolet ( UV ) rays. Stratospheric ozone depletion leads to an increase in UV -B that reach the earth's surface, where it can disrupt biological processes and damage a number of materials

Explanation: Hope This Helps!

The pilot should leave the shore at an angle of 14.04° in order to go directly to the child.

To find the angle, we can use the Pythagorean Theorem and trigonometry.

First, we need to find the distance between the child and the boat dock. Using the Pythagorean Theorem, we get:

d = √((200 m)^2 + (1500 m)^2) = 1520.69 m

Next, we need to find the time it will take for the child to reach the boat dock. Since the child is being carried by the current at a speed of 2.0 m/s, we can use the formula:

t = d/v = 1520.69 m / 2.0 m/s = 760.34 s

Now, we need to find the distance the boat will travel in this time. Since the boat has a speed of 8.0 m/s with respect to the water, we can use the formula:

d = v*t = 8.0 m/s * 760.34 s = 6082.72 m

Finally, we can use trigonometry to find the angle at which the pilot should leave the shore. Using the formula:

tan(θ) = opposite/adjacent = 200 m / 6082.72 m = 0.0329

θ = tan^-1(0.0329) = 14.04°

Therefore, the pilot should leave the shore at an angle of 14.04° in order to go directly to the child.

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Answer:

uhhh

Explanation:

Gino should tell his partner that she should have only done four quarter turns and should have finished the dance after 32 counts. This would have resulted in her facing only two walls at the end.

Quarter is a term used to describe the amount of rotation an object has undergone when it does a full turn. A quarter-turn is the equivalent of 90 degrees. Quarter are commonly used to measure the rotation of a wheel, a lever, a bolt, or any other object that can be rotated. It is also used in architecture to describe the amount of rotation of a staircase or other structure. In engineering, quarter-turns are used to measure the amount of torque that is being applied to a mechanism or device. Quarter are also used to measure the amount of rotation when adjusting the settings of a device.

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The time taken by Super Mario  is 2.91 seconds to reach the mystery block.

To find the time it takes for Super Mario to reach the mystery block, we can use the kinematic equation:

∆y = v0t + (1/2)at2

Where ∆y is the change in a vertical position, v0 is the initial vertical velocity, a is the acceleration due to gravity, and t is the time.

Since the mystery block is 8.2 m above Mario's head, ∆y = 8.2 m. The initial vertical velocity, v0, is 0 m/s since Mario is starting from rest. The acceleration due to gravity in the Mushroom Kingdom, gmk, is 1/5th of that on Earth, so

a = (1/5)g = (1/5)(9.8 m/s2)

a = 1.96 m/s2.

Plugging these values into the equation, we get:

8.2 m = (0 m/s)t + (1/2)(1.96 m/s2)t2

Simplifying and rearranging, we get:

t2 = (8.2 m)/(0.98 m/s2)

Taking the square root of both sides, we get:

t = √((8.2 m)/(0.98 m/s2)) = 2.91 s

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At a pace of 8 km/hr, it would take the roller skater 3.125 hours to complete 25 km.

To determine how long it would take a roller skater to travel 25 km if their speed is 8 km/hr, we can use the formula:

time = distance / speed

In this case, the distance is 25 km and the speed is 8 km/hr. Substituting these values into the formula, we get:

time = 25 km / 8 km/hr

Simplifying, we get:

time = 3.125 hours

Therefore, it would take the roller skater 3.125 hours to travel 25 km at a speed of 8 km/hr. It's important to note that this is assuming a constant speed throughout the journey, and not taking into account any breaks or rest stops the skater may need to take.

To learn more about  speed refer to:

brainly.com/question/17661499

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Answer:

490 W

Explanation:

F = ma = (50 kg)(9.8 m/s²) = 490 N    (Weight = W = mg)

Work = W = Fd = (490 N)(5 m) = 2450 J

Power = W/t = 2450 J / 5 s = 490 J/s = 490 W  (watts)