Is Work Always Positive in Linear and Rotational Cases?

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A) Questions, Equations & Attempts on answering

1) If I'm correct, for linear cases, Work= Fs,

F= Constant Force
s= Displacement

where Work can= negative if displacement ends up in the opposite direction, am I right?

2) Rotational Work= Fs

= Frφ

= τφ,

F= Constant Force
s= Displacement
r= Displacement for rotational work
φ= Resultant Angle
τ= Torque,and the case being considered,

220px-Work_on_the_lever_arm.jpg
.

Just confirming, say, at point F, this line, r's been spun -360°x10 times, if F increases, does that mean Rotational Work increases?

3) For 2), as r's been spun 360°x10 times counter clockwise, it won't be a negative work value would it?
 
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inv said:
Just confirming, say, at point F, this line, r's been spun -360°x10 times, if F increases, does that mean Rotational Work increases?

3) For 2), as r's been spun 360°x10 times counter clockwise, it won't be a negative work value would it?
If the force points in the direction of the displacement, then the work done will be positive; if it points opposite to the displacement, then negative.