Find mass given acceleration and upward force

AI Thread Summary
To find the mass of a body given an upward force of 10N, an unknown downward force (mg), and a downward acceleration of 5 m/s², the resultant force must first be calculated. Using the equation F = ma, the net force can be determined by subtracting the upward force from the downward force. The equation W = mg relates weight to mass, allowing for the calculation of mass once the resultant force is known. The correct approach involves applying the principle that the sum of forces equals mass times acceleration. This method will yield the mass of the body accurately.
zonesthesia93
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Homework Statement


Find the mass of the body when:
upward force is 10N
downward force unknown (mg N)
acceleration 5ms^-2 downwards


Homework Equations


F=ma
W=mg


The Attempt at a Solution


Need to work out the resultant force?? Then find the mass from there...


Thank you!
 
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That's correct.
Remember that \sum \vec{F}=m\vec{a}
 
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