MHB Finding revolution/minute of a wheel traveling in a speed of 15 miles/hour

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To find the angular speed of a truck's wheels traveling at 15 miles per hour with 32-inch diameter wheels, the relationship between linear speed and angular speed is crucial. The formula v = rω can be used, where v is linear speed, r is the radius, and ω is angular speed in radians per minute. Given the diameter, the radius is 16 inches, which needs to be converted to feet for consistency with the speed unit. After calculating the angular speed, the number of revolutions per minute can be determined by converting radians to revolutions. Understanding the distinction between linear and angular speed is essential for solving these types of problems effectively.
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A truck with 32- inch- diameter wheels is traveling in a speed of 15 miles/hour. Find the angular speed of the wheels in radians/minute. How many revolutions per minute does the wheel make?

My teacher mentions that we are trying to find the angular speed in this. Another question is how do I distinguish using angular or linear speed/formula for this equation? I know that angular speed = theta/time and linear speed = arclength/time, but when he explained the question, he made up a newer looking equation: v = (2pi(r)w)/theta. I don't understand this at all and how to get the answer.
 
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Let's begin with the equation for linear distance, speed and time:

$$d=vt$$

When the truck's wheel moves through an angle $\theta$, then the truck will move a linear distance equal to:

$$d=r\theta$$

This comes from the arc-length of a circular sector.

And so we have:

$$r\theta=vt$$

Now, the angular velocity $\omega$ is defined as the change of the angle $\theta$ with respect to time, and for constant speeds, this is:

$$\omega\equiv\frac{\theta}{t}$$

Now, recall we have:

$$r\theta=vt$$

Dividing through by $t$, we obtain:

$$v=r\frac{\theta}{t}=r\omega$$

or:

$$\omega=\frac{v}{r}$$

You are given $v$ and $r$ and so you can find $\omega$ from this formula, but be mindful of your units, because $v$ is given in miles per hour, but you want time in minutes. Can you proceed?
 
Sorry it took awhile to reply but yes! That really helped a lot! Thank you so much for that! I asked my friend who's taking a physics class and he mentioned that the linear speed formula is similar to something he learned, except it's not:

$$v=(radius(theta))/time$$

but

$$v=distance/radius$$

I'm still very edgy and somewhat having trouble with trigonometry, my teacher's back is always blocking what he's doing.
 
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