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This coursework question I am faced with is very specific and quite difficult to explain so I have attached the question. The writing on the side is not that important so dont try and make sense of it.
The question asks to find the angular velocity of 2 planetary gears (which are connected by a quarter circle plate) rotating about a larger Sun gear. The plate is attached to the centre of the planetary gears at the corners where the arc and the radii meet, with the 2 radii converging at the centre of the Sun gear.
the mass of the 2 planetary gears are 2kg
the mass of the quarter circle is 6kg
the radius of the Sun gear is 0.15m
the radius of the planetary gears are 0.075m
things I worked out from that:
Radius of quarter circle = 0.225m
Centre of mass of the quarter circle = 0.135m from the pinnacle.
Initially, the quarter circle occupies quadrant 1 entirely, with the planetary gears connected at the corners.
The question asks to find the angular velocity of the planetary gears when the quarter circle moves through Pi/2 rad clockwise to occupy quadrant 4 entirely.
This is an energy conservation question, however I'm struggling with the relevant circular motions.
KE + PE + RE=constant
I found the centre of mass of the quarter circle and thus found the initial energy of the system but wasnt sure what to do next.
I want to find the final KE but I am not sure how to approach this. I know gravity is working tangentially to the Sun gear, but how do you incorporate that into the relevant KE equation?
Thanks in advance
The question asks to find the angular velocity of 2 planetary gears (which are connected by a quarter circle plate) rotating about a larger Sun gear. The plate is attached to the centre of the planetary gears at the corners where the arc and the radii meet, with the 2 radii converging at the centre of the Sun gear.
the mass of the 2 planetary gears are 2kg
the mass of the quarter circle is 6kg
the radius of the Sun gear is 0.15m
the radius of the planetary gears are 0.075m
things I worked out from that:
Radius of quarter circle = 0.225m
Centre of mass of the quarter circle = 0.135m from the pinnacle.
Initially, the quarter circle occupies quadrant 1 entirely, with the planetary gears connected at the corners.
The question asks to find the angular velocity of the planetary gears when the quarter circle moves through Pi/2 rad clockwise to occupy quadrant 4 entirely.
This is an energy conservation question, however I'm struggling with the relevant circular motions.
KE + PE + RE=constant
I found the centre of mass of the quarter circle and thus found the initial energy of the system but wasnt sure what to do next.
I want to find the final KE but I am not sure how to approach this. I know gravity is working tangentially to the Sun gear, but how do you incorporate that into the relevant KE equation?
Thanks in advance
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