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CAN Someone Please Help on this physics problem?

While driving at 27 m/s, the driver steps in the gas to beat a yellow light. They accelerate at 2.8 m/s^2. They drive through the intersection that is 55 m long. How fast were they going after going through the intersection? Remember to show work including know values, unknown values, equation used, plugging into equation and displayed answer with proper units.

1 Answer

4 votes

Answer:

the driver's speed after going through the intersection is approximately 32.2 m/s.

Step-by-step explanation:

To determine the speed of the driver after going through the intersection, we can use the kinematic equation:

v^2 = u^2 + 2as

Where: v = final velocity (unknown)

u = initial velocity = 27 m/s

a = acceleration = 2.8 m/s^2

s = distance traveled = 55 m

First, let's calculate the value of v^2: v^2 = (27 m/s)^2 + 2(2.8 m/s^2)(55 m)

v^2 = 729 m^2/s^2 + 2(2.8 m/s^2)(55 m)

v^2 = 729 m^2/s^2 + 308 m^2/s^2

v^2 = 1037 m^2/s^2

Now, let's find the square root of both sides to solve for v: v = √(1037 m^2/s^2)

v ≈ 32.2 m/s

Therefore, the driver's speed after going through the intersection is approximately 32.2 m/s.

Please note that rounding the final answer to two decimal places is a common practice, but you can use more decimal places if necessary.

User Rohit Pradhan
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