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A car going 40mph accelerates to pass a truck. Five seconds later the car is going 90mph. Calculate the acceleration of the car.

User Nocksock
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1 Answer

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Final answer:

The acceleration of the car is calculated using the formula a = Δv / t. The car's velocity changes from about 17.88 m/s to 40.23 m/s over 5 seconds, resulting in an average acceleration of 4.47 m/s².

Step-by-step explanation:

To calculate the acceleration of the car, we need to use the following kinematic formula:

a = Δv / t

Where:
a is the acceleration,
Δv is the change in velocity, and
t is the time taken for this change.

The car goes from 40mph to 90mph, which in meters per second (m/s) is a change from approximately 17.88 m/s (40mph) to 40.23 m/s (90mph). To convert from miles per hour to meters per second, you can multiply by 0.44704 (since 1 mph is approximately equal to 0.44704 m/s).

Here is the calculation:
Δv = 40.23 m/s - 17.88 m/s = 22.35 m/s
t = 5 s

Now we plug these values into the formula to find the acceleration:

a = 22.35 m/s / 5 s = 4.47 m/s²

The average acceleration of the car is 4.47 m/s².

User Abhijeet Mallick
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