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[supernoy]

how to receive verification message from rumble.com?

 

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We can use the standard normal distribution to solve this problem. We know that the mean of the distribution is 75, and the standard deviation is 9.5. We can standardize the score using the formula:

z = (x - mu) / sigma

where x is the score we want to find, mu is the mean, sigma is the standard deviation, and z is the corresponding z-score.

To find the minimum score required to be in the top 2.5%, we need to find the z-score that corresponds to the 97.5th percentile. We can use a standard normal distribution table, or a calculator with a normal distribution function, to find this z-score.

Using a standard normal distribution table, we find that the z-score that corresponds to the 97.5th percentile is approximately 1.96.

Now we can use the formula for z-score to solve for x:

1.96 = (x - 75) / 9.5

Multiplying both sides by 9.5, we get:

x - 75 = 18.62

Adding 75 to both sides, we get:

x = 93.62

Therefore, a student would need to obtain a score of at least 93.62 to be part of the top 2.5%.

 

[supernoy]

the ratio of students to professional is 4:5. if there are 45 participants together, how many of them are professionals?

 

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Let's represent the number of students and professionals as 4x and 5x, respectively.

We know that the total number of participants is 45, so we can write an equation:

4x + 5x = 45

Simplifying:

9x = 45

Dividing both sides by 9:

x = 5

Now we can find the number of professionals by multiplying 5x (or 5 times the number of professionals) by 5:

5x = 5(5) = 25

Therefore, there are 25 professionals among the 45 participants.

 

[supernoy]

Let's represent the number of students and professionals as 4x and 5x, respectively.

We know that the total number of participants is 45, so we can write an equation:

4x + 5x = 45

Simplifying:

9x = 45

Dividing both sides by 9:

x = 5

Now we can find the number of professionals by multiplying 5x (or 5 times the number of professionals) by 5:

5x = 5(5) = 25

Therefore, there are 25 professionals among the 45 participants.

A company is selling calculators for $100 each. How many should it sell to break even if it costs $10 to manufacture each calculator in addition to a

fixed cost of $4500?

 

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A company is selling calculators for $100 each. How many should it sell to break even if it costs $10 to manufacture each calculator in addition to a

fixed cost of $4500?

To break even, the total revenue from selling calculators should equal the total cost of making them.

The cost of making each calculator is $10 and there is a fixed cost of $4500. So, the total cost of making ‘x’ calculators is:

Total cost = $4500 + $10x

The revenue from selling each calculator is $100, so the total revenue from selling ‘x’ calculators is:

Total revenue = $100x

To break even, the total revenue should equal the total cost:

$4500 + $10x = $100x

Simplifying:

$4500 = $90x

x = 50

Therefore, the company needs to sell 50 calculators to break even.

 

[supernoy]

To break even, the total revenue from selling calculators should equal the total cost of making them.

The cost of making each calculator is $10 and there is a fixed cost of $4500. So, the total cost of making ‘x’ calculators is:

Total cost = $4500 + $10x

The revenue from selling each calculator is $100, so the total revenue from selling ‘x’ calculators is:

Total revenue = $100x

To break even, the total revenue should equal the total cost:

$4500 + $10x = $100x

Simplifying:

$4500 = $90x

x = 50

Therefore, the company needs to sell 50 calculators to break even.

The sale price of a book after a 25% discount is $40. What was its original price?

 

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The sale price of a book after a 25% discount is $40. What was its original price?

Let the original price of the book be "x".

If the book was sold at a 25% discount, then the sale price would be 75% of the original price:

Sale price = 75% of x

$40 = (75/100)x

Solving for x:

x = ($40 x 100) / 75

x = $53.33 (rounded to two decimal places)

Therefore, the original price of the book was $53.33.

 

[supernoy]

Let the original price of the book be "x".

If the book was sold at a 25% discount, then the sale price would be 75% of the original price:

Sale price = 75% of x

$40 = (75/100)x

Solving for x:

x = ($40 x 100) / 75

x = $53.33 (rounded to two decimal places)

Therefore, the original price of the book was $53.33.

The velocity e of a particle moving on the horizontal axis is given by a function of time t as:

v = 4 — 3t^2

where v is in meters per second and t is in seconds. At time t = 0 s, the particle is at x = 0 meters. Consider the direction to the right as the positive

direction.

Which of the following is true about the particle at time t = 2.0 s?

 

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The velocity e of a particle moving on the horizontal axis is given by a function of time t as:

v = 4 — 3t^2

where v is in meters per second and t is in seconds. At time t = 0 s, the particle is at x = 0 meters. Consider the direction to the right as the positive

direction.

Which of the following is true about the particle at time t = 2.0 s?

To determine the position of the particle at time t = 2.0 s, we need to integrate the given velocity function from t = 0 to t = 2.0 s:

∫v dt = ∫(4 - 3t^2) dt

= [4t - t^3] from t = 0 to t = 2.0 s

= [4(2.0) - (2.0)^3] - [4(0) - (0)^3]

= 8.0 - 8.0

= 0

Therefore, the position of the particle at time t = 2.0 s is 0 meters, which means that it is back at its initial position.

 

[supernoy]

To determine the position of the particle at time t = 2.0 s, we need to integrate the given velocity function from t = 0 to t = 2.0 s:

∫v dt = ∫(4 - 3t^2) dt

= [4t - t^3] from t = 0 to t = 2.0 s

= [4(2.0) - (2.0)^3] - [4(0) - (0)^3]

= 8.0 - 8.0

= 0

Therefore, the position of the particle at time t = 2.0 s is 0 meters, which means that it is back at its initial position.

According to an observer on Earth, two spaceships A and B are

moving towards each other. Spaceship A is moving at 0.80c to the

observer's left while spaceship B is moving at 0.65c to her right. An

astronaut in spaceship A turns a laser on for an experiment.

Relative to an astronaut in spaceship B, how fast are the photons

coming from the laser in spaceship A travelling? Express the speed in

terms of c

 

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According to an observer on Earth, two spaceships A and B are

moving towards each other. Spaceship A is moving at 0.80c to the

observer's left while spaceship B is moving at 0.65c to her right. An

astronaut in spaceship A turns a laser on for an experiment.

Relative to an astronaut in spaceship B, how fast are the photons

coming from the laser in spaceship A travelling? Express the speed in

terms of c

According to the theory of relativity, the speed of light is the same for all observers, regardless of their relative velocities. Therefore, the speed of the photons coming from the laser in spaceship A would be the same for an astronaut in spaceship B as it is for the observer on Earth.

This means that the speed of the photons coming from the laser in spaceship A relative to an astronaut in spaceship B would also be equal to the speed of light, c.

 

[supernoy]

According to the theory of relativity, the speed of light is the same for all observers, regardless of their relative velocities. Therefore, the speed of the photons coming from the laser in spaceship A would be the same for an astronaut in spaceship B as it is for the observer on Earth.

This means that the speed of the photons coming from the laser in spaceship A relative to an astronaut in spaceship B would also be equal to the speed of light, c.

New'ton's second law of motion states the equation below:

summation of F = ma

where F is the total external force acting on the body, m is the mass and a is the acceleration of the body.

Describe Newton's second law in terms of change in momentum.

 

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New'ton's second law of motion states the equation below:

summation of F = ma

where F is the total external force acting on the body, m is the mass and a is the acceleration of the body.

Describe Newton's second law in terms of change in momentum.

View attachment 2631731

Newton's second law of motion can also be described in terms of the change in momentum. The momentum of an object is defined as the product of its mass and velocity, and is given by the equation:

p = mv

where p is momentum, m is mass, and v is velocity.

If a force F is applied to an object for a time interval t, the force can be expressed as:

F = Δp/Δt

where Δp is the change in momentum and Δt is the time interval.

Rearranging this equation gives:

Δp = FΔt

This equation shows that the change in momentum of an object is equal to the force applied to the object multiplied by the time over which the force is applied.

Using the definition of acceleration, a = Δv/Δt, we can write F = ma as:

F = mΔv/Δt

Multiplying both sides by Δt gives:

FΔt = mΔv

But Δp = mΔv, so we can write:

FΔt = Δp

This is the same equation we obtained earlier. Therefore, Newton's second law can be described as the relationship between the force applied to an object and the resulting change in momentum of the object.

 

[supernoy]

Newton's second law of motion can also be described in terms of the change in momentum. The momentum of an object is defined as the product of its mass and velocity, and is given by the equation:

p = mv

where p is momentum, m is mass, and v is velocity.

If a force F is applied to an object for a time interval t, the force can be expressed as:

F = Δp/Δt

where Δp is the change in momentum and Δt is the time interval.

Rearranging this equation gives:

Δp = FΔt

This equation shows that the change in momentum of an object is equal to the force applied to the object multiplied by the time over which the force is applied.

Using the definition of acceleration, a = Δv/Δt, we can write F = ma as:

F = mΔv/Δt

Multiplying both sides by Δt gives:

FΔt = mΔv

But Δp = mΔv, so we can write:

FΔt = Δp

This is the same equation we obtained earlier. Therefore, Newton's second law can be described as the relationship between the force applied to an object and the resulting change in momentum of the object.

In a rare event that only happens once every few hundred years, a pair of comets will be visible in the night sky. Comet A will be travelling at a speed of

0.40c and Comet B will travel in the same direction at 0.90c, both relative to Earth's ground.

What is the relative speed of each comet in the other's reference frame?

 

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In a rare event that only happens once every few hundred years, a pair of comets will be visible in the night sky. Comet A will be travelling at a speed of

0.40c and Comet B will travel in the same direction at 0.90c, both relative to Earth's ground.

What is the relative speed of each comet in the other's reference frame?

According to the theory of relativity, the relative velocity between two objects depends on the reference frame from which it is being observed.

Let's consider Comet A's reference frame. In this reference frame, Comet A is at rest and Comet B is moving towards it with a velocity of:

v_AB = 0.90c - 0.40c = 0.50c

Now, let's consider Comet B's reference frame. In this frame, Comet B is at rest and Comet A is moving towards it with a velocity of:

v_BA = -v_AB = -0.50c

Therefore, the relative speed of Comet B in Comet A's reference frame is 0.50c, and the relative speed of Comet A in Comet B's reference frame is -0.50c (or 0.50c in the opposite direction).

 

[supernoy]

According to the theory of relativity, the relative velocity between two objects depends on the reference frame from which it is being observed.

Let's consider Comet A's reference frame. In this reference frame, Comet A is at rest and Comet B is moving towards it with a velocity of:

v_AB = 0.90c - 0.40c = 0.50c

Now, let's consider Comet B's reference frame. In this frame, Comet B is at rest and Comet A is moving towards it with a velocity of:

v_BA = -v_AB = -0.50c

Therefore, the relative speed of Comet B in Comet A's reference frame is 0.50c, and the relative speed of Comet A in Comet B's reference frame is -0.50c (or 0.50c in the opposite direction).

three vectors are define as

A = 2i-3j
B = -i+5j
c = -4k

then, what is the value of expression
A.(C X B)

 

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three vectors are define as

A = 2i-3j
B = -i+5j
c = -4k

then, what is the value of expression
A.(C X B)

The cross product of vectors B and C is given by:

B x C = (5j)(-4k) - (-k)(-i) = 20i + 4j

Taking the dot product of A with B x C gives:

A . (B x C) = (2i - 3j) . (20i + 4j)

= 2(20) + (-3)(4)

= 40 - 12

= 28

Therefore, the value of the expression A . (C x B) is 28.

 

[supernoy]

The cross product of vectors B and C is given by:

B x C = (5j)(-4k) - (-k)(-i) = 20i + 4j

Taking the dot product of A with B x C gives:

A . (B x C) = (2i - 3j) . (20i + 4j)

= 2(20) + (-3)(4)

= 40 - 12

= 28

Therefore, the value of the expression A . (C x B) is 28.

An object is placed 40 cm in front of a convex mirror with 80-cm

radius.

describes the image formed

 

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An object is placed 40 cm in front of a convex mirror with 80-cm

radius.

describes the image formed

Using the mirror formula for a convex mirror, 1/f = 1/v + 1/u, where f is the focal length, u is the object distance, and v is the image distance, we can find the image distance as:

1/f = 1/v + 1/u

For a convex mirror, the focal length is positive and given by f = R/2, where R is the radius of curvature, which is positive for a convex mirror.

Substituting f = 80 cm and u = -40 cm (since the object is placed in front of the mirror), we get:

1/80 = 1/v - 1/40

Solving for v, we get:

v = 53.3 cm

Since the image distance is positive, the image is formed behind the mirror, and is virtual and diminished in size compared to the object. The negative sign of the object distance indicates that the object is placed in front of the mirror.

Therefore, the image formed is virtual, diminished, and located 53.3 cm behind the mirror.

 

[supernoy]

Using the mirror formula for a convex mirror, 1/f = 1/v + 1/u, where f is the focal length, u is the object distance, and v is the image distance, we can find the image distance as:

1/f = 1/v + 1/u

For a convex mirror, the focal length is positive and given by f = R/2, where R is the radius of curvature, which is positive for a convex mirror.

Substituting f = 80 cm and u = -40 cm (since the object is placed in front of the mirror), we get:

1/80 = 1/v - 1/40

Solving for v, we get:

v = 53.3 cm

Since the image distance is positive, the image is formed behind the mirror, and is virtual and diminished in size compared to the object. The negative sign of the object distance indicates that the object is placed in front of the mirror.

Therefore, the image formed is virtual, diminished, and located 53.3 cm behind the mirror.

A +Q and a +2Q point charges were placed at the vertices of an

equilateral triangle of side a, A third —2Q charge is placed at point P.
What is the work done by an external force in moving —2Q from a position at

infinity to P?