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A monorail starts from rest, accelerates at a rate of 2.2 m/s² for 10 s, runs at a constant speed for 74 s, and then slows down at a rate of 1.5 m/s². What is the total displacement during the entire motion?

a) Positive displacement

b) Zero displacement

c) Negative displacement

d) Unable to determine

User Swapnali
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1 Answer

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Final answer:

The total displacement during the entire motion of the monorail is -35 m. Therefore, the correct answer is c) Negative displacement.

Step-by-step explanation:

To find the total displacement during the entire motion, we need to consider each phase of the monorail's motion separately.

First phase: Acceleration phase

The monorail starts from rest and accelerates at a rate of 2.2 m/s² for 10 s. During this phase, we can find the displacement using the equation:

displacement = (initial velocity * time) + ((1/2) * acceleration * time^2)

Since the initial velocity is 0, the equation simplifies to:

displacement = (1/2) * acceleration * time^2

Substituting the given values, we get:

displacement = (1/2) * 2.2 * (10)^2 = 110 m

Second phase: Constant speed

During this phase, the monorail runs at a constant speed for 74 s. Since speed is constant, the displacement is simply:

displacement = speed * time = (speed of the monorail) * 74

Third phase: Deceleration phase

The monorail slows down at a rate of 1.5 m/s². Using the same equation as in the acceleration phase, we can find the displacement:

displacement = (1/2) * acceleration * time^2

Substituting the given values, we get:

displacement = (1/2) * (-1.5) * (10)^2 = -75 m

Adding up the displacements from each phase, we get a total displacement of 110 m + 0 m + (-75 m) = 35 m.

Therefore, the correct answer is c) Negative displacement.

User Jayant Agrawal
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