There is a wind tunnel force balance allowing the
measurement of the drag force resultant at point A of a test object in the air
stream from an arm and lever system mounted on a pivoting point O and
pressing onto a force sensor at point B.
1) What will be magnitude of the force transmitted into the sensor at B if the air
flow results in creating a lift force of 1.75 N and a drag force of 1.20 N?
I couldn't paste in the picture it wouldn't let me. but there is a 90 degree lever with the first part of the lever being vertical in the direction of lift and is 1.2m long. There is then a pivot, O, and to the right of that at 90 degrees is a horizontal part of the lever and is 0.5m long. sensor B is underneath this part so that when drag occurs it will push on the lever and push down onto B.
2) Calculate the horizontal component Ox and vertical component, Oy of the transmitted force in pivoting point O.
(Consider the coordinate system used to be positive in the direction against the airflow for the x component, and positive in the upward direction for y)
Give your answer in Newtons (N)
The Attempt at a Solution
question 1 - The sensor is used to measure lift so is the answer simply 1.20N?
I tried resolving the force and then did some moments but then realised I only need an answer in Newtons and I would get an answer in N/m.
question 2 - is it -1.20 since the force transmitted is in the opposite direction to airflow? and vertical component 0? I'm confused because the lengths of the lever arms seem to be irrelevant.
This is my first post, thank you for reading and helping if you can!
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