Answer
The speed of a point at the front edge of the wheel is 28 m/s
Work Step by Step
Since the wheel is rolling at 20 m/s, then every point on the wheel has a horizontal component of speed that is equal to 20 m/s and directed forward.
If the wheel is rolling at 20 m/s, then every point on the edge of the wheel is rotating with a speed of 20 m/s. From this rotation, a point at the front edge of the wheel has a vertical component of speed that is 20 m/s directed straight down.
A point at the front edge of the wheel has a horizontal component of speed equal to 20 m/s and a vertical component of speed equal to 20 m/s. We can find the speed of a point at the front edge of the wheel.
$v = \sqrt{(v_x)^2+(v_y)^2}$
$v = \sqrt{(20~m/s)^2+(20~m/s)^2}$
$v = 28~m/s$
The speed of a point at the front edge of the wheel is 28 m/s.
