PH-UY 1013 Lecture Notes - Lecture 22: Momentum, Unit Vector, Dot Product

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19 Apr 2018

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Propeller is rotating, linear momentum is not conserved, angular momentum is conserved. Angular momentum of point masses moving in a straight line. Something moving in a straight line still has angular momentum (rotate ccw=mvd, rotate cw=- mvd) Righty tighty, lefty loosey (tighty is going in, loosey is coming out) Just multiply by k hat, the unit vector in +z direction. If (cid:882)(cid:1867)(cid:1870) (cid:883)8(cid:882), we need to find the direction of (cid:1827) (cid:1828) This limits all possibilities to 2, each of which is the regular (negative, opposite) of the other: thumb in direction being tested, fingers point towards a (cid:1827) (cid:1828) (cid:1827)and (cid:1827) (cid:1828) (cid:1828) Rh (right hand) rule helps decide direction of (cid:1827) (cid:1828: close fingers. If they move towards b, then thumb is in direction of (cid:1827) (cid:1828) (cid:1828) (cid:1827)= (cid:1827) (cid:1828) (cid:1827) (cid:1827)= (cid:1827) (cid:1827) (cid:1827) (cid:1827)+(cid:1827) (cid:1827)=(cid:882) (cid:1827) (cid:1827)=(cid:882)

Related Questions

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PH-UY 1013 Lecture Notes - Lecture 22: Momentum, Unit Vector, Dot Product

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