Relative motion on a conveyor belt

AI Thread Summary
The discussion focuses on determining the velocity of sand relative to conveyor belt B as it lands, given the constant velocities of both belts. The velocity of sand on belt A is -6 ft/s horizontally, while belt B moves at 8 ft/s. The challenge arises in calculating the correct angle and velocity of the sand as it transitions from belt A to belt B, particularly due to the change in motion when the sand falls 5 feet. The user attempts to apply trigonometric analysis to find the angle and velocity components but encounters difficulties with the projectile motion involved. Ultimately, the calculated velocity of the sand relative to belt B is 20.1 ft/s at an angle of 85.1 degrees.
JJBladester
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Homework Statement


Belt A conveys sand with a velocity of 6.0 ft/s (constant). The velocity of belt B is 8 ft/s (constant). Determine the velocity of the sand relative to B as it lands on belt B. Answer: VS/B=20.1 ft/s at 85.1 degrees

conveyor%20belt.jpg


Homework Equations



VS/B = VS-VB
(Velocity of sand relative to belt B = velocity of sand as it hits belt B - velocity of belt B)

The Attempt at a Solution



VB=8cos(15°)+8sin(15°) = -7.727\hat{i}+2.071\hat{j}(ft/s)

My trouble is with finding VS. I know that on the horizontal section of belt A, the sand's velocity (VS) is -6\hat{i}+0\hat{j}(ft/s).

When the sand hits the bend where belt A is not horizontal anymore, but starts to bend into belt B, the velocity of the sand changes.

I think I'm stuck on the trig of what the angle is and how the 5ft contributes to finding the correct angle that the sand runs into belt B.
 
Physics news on Phys.org
when the sand leaves the belt A, its in free fall. use projectile motion analysis to find
the velocity 5 ft below, when it hits belt B.
 
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