Find mass given acceleration and upward force

Thread starter zonesthesia93
Start date Oct 14, 2011
Tags

Acceleration Force Mass

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.

Oct 14, 2011

zonesthesia93

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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Oct 14, 2011

DiracRules

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

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