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A truck with 28-In.-diameter wheels is traveling at 45 mph.

How many revolutions per minute do the wheels make?rpm

What is the angular speed of the wheels In radians/min?rad/min

Round answers to 2 decimal places

1 Answer

6 votes

Answer:

To find the number of revolutions per minute (RPM) the wheels make, we first need to find the circumference of the wheel. We can use the equation:

Circumference = 2 * pi * radius

The diameter of the wheel is 28 inches, so we can find the radius by dividing the diameter by 2:

Radius = 28 inches / 2 = 14 inches

Now we can find the circumference of the wheel:

Circumference = 2 * pi * 14 inches = 87.96 inches

To find the number of revolutions per minute, we need to know how many inches the wheel travels in one minute, we can convert 45 mph to inches per minute by multiplying 45 mph by 1.46667 (1 mph = 1.46667 inches/s)

inches per minute = 45 * 1.46667 = 66.00015 inches

So we can find the number of revolutions per minute by dividing the distance traveled per minute by the circumference of the wheel:

RPM = inches per minute / circumference

RPM = 66.00015 inches / 87.96 inches = 0.75 rev/min

To find the angular speed of the wheels in radians per minute, we can use the equation:

Angular speed = 2 * pi * RPM

Angular speed = 2 * pi * 0.75 rev/min = 4.71 rad/min

So the angular speed of the wheels in radians per minute is 4.71 rad/min (rounded to 2 decimal places)

User Andy Librian
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