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How long would it take a 1.50 x 105 kg airplane with engines that produce 100 MW of power to reach a speed of 250 m/s and an altitude of 12.0 km if air resistance were negligible

User Kovaxis
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2 Answers

4 votes

Final answer:

To find the time it would take for the airplane to reach a speed of 250 m/s and an altitude of 12.0 km, we use the equations of motion. First, we find the time for the speed of 250 m/s, which is approximately 0.375 seconds. Then, we find the time for the altitude of 12.0 km, which is approximately 6 seconds.

Step-by-step explanation:

To find the time it would take for the airplane to reach a speed of 250 m/s and an altitude of 12.0 km, we need to use the equations of motion.

First, let's find the time it takes for the airplane to reach the speed of 250 m/s. We can use the equation:

v = u + at

Where v is the final velocity, u is the initial velocity, a is the acceleration, and t is the time taken.

Given that the initial velocity is 0 m/s, the final velocity is 250 m/s, and the acceleration is unknown, we can rearrange the equation to solve for time:

t = (v - u) / a

Since the acceleration is constant, we can use the formula:

a = P / m

Where P is the power and m is the mass.

Given that the power is 100 MW and the mass is 1.50 x 10^5 kg, we can substitute these values into the equation:

a = 100 MW / (1.50 x 10^5 kg)

Be sure to convert the power from MW to W by multiplying it by 10^6, so the equation becomes:

a = (100 x 10^6 W) / (1.50 x 10^5 kg)

Simplify the equation to find the acceleration:

a = 666.67 m/s^2

Now substitute the values of velocity and acceleration into the equation:

t = (250 m/s - 0 m/s) / 666.67 m/s^2

Solve for time:

t = 0.375 s

Therefore, it would take approximately 0.375 seconds for the airplane to reach a speed of 250 m/s.

To find the time it takes for the airplane to reach an altitude of 12.0 km, we need to use the equation:

s = ut + (1/2)at^2

Where s is the displacement, u is the initial velocity, a is the acceleration, and t is the time taken.

Given that the acceleration is the same as before (666.67 m/s^2), the initial velocity is 0 m/s, and the displacement is 12.0 km (which is equal to 12000 m), we can rearrange the equation to solve for time:

t = sqrt((2s) / a)

Substitute the values into the equation:

t = sqrt((2 x 12000 m) / 666.67 m/s^2)

Calculate the square root and simplify the equation:

t = sqrt(36)

t = 6 s

Therefore, it would take approximately 6 seconds for the airplane to reach an altitude of 12.0 km.

User EngineerDave
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5.6k points
3 votes

Step-by-step explanation:

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How long would it take a 1.50 x 105 kg airplane with engines that produce 100 MW of-example-1
User Rabs G
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