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You get in your car to drive to school at 7:33 am and drive 10 miles north at a constant speed until 7:45

am, when you realize you left your homework on the kitchen table. You turn around and drive 10 miles
south back to your house and retrieve your homework at 8:00 am. You get back in the car and drive 15
miles north to school at a constant speed arriving at school at 8:29 am sharp, just in time to make it
before the bell rings.
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1 Answer

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Answer:

5.) 16.8 m/s

6.) 16.1 mph

7.) Moving fast.

Step-by-step explanation:

5.) From the question, the total time will be:

7:33 am to 7:45 am = 12 minutes

As the car turns around,

7 : 45 am to 8 : 00am = 15 minutes

As you get back in the car and drive 15

miles north to school at a constant speed arriving at school at 8:29 am

8:00am to 8:29 am = 29 minutes

Total time = 12 + 15 + 29 = 56 minutes

Convert the minutes to second by multiplying the result by 60

Total time = 56 × 60 = 3360 seconds

Total distance covered will be

10 miles + 10 miles + 15 miles = 35 miles

Convert mile to meter by multiplying the result by 1609.344

35 × 1609.344 = 56327.04

Speed is a scale quantity. It only involves magnitude but no direction.

Average speed = total distance/total time

Average speed = 56327.04/3360

Average speed = 16.764 m/s

6.) Velocity = displacement/time

Velocity is a vector quantity. We will consider both the magnitude and direction

Total displacement = 10 miles - 10 miles + 15 miles = 15 miles.

Total time = 56 minutes

Convert minutes to hours by dividing it by 60

Total time = 56/60 = 0.93 hours

Substitute the time and displacement into the formula

Velocity = 15/0.93 = 16.07 mph

7.) . If you looked at your speedometer on your drive to school and it read 30mph, this value describes you move with a fast speed.

User MinceMan
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