100924-opp

# 100924-opp - 9/24/10 Physics 121 1 9/24/10 Physics 121 3...

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Unformatted text preview: 9/24/10 Physics 121 1 9/24/10 Physics 121 3 Why footholds? a=F 9/24/10 Physics 121 net m 4 9/24/10 Physics 121 6 9/24/10 Physics 121 7 We’re only considering horizontal motions and pForces! B A f table f table A B A NB 9/24/10 A B N hand A Physics 121 NA B 8 9/24/10 Physics 121 10 9/24/10 Physics 121 11 Assuming no friction! A+B N hand A+ B a A+ B = 9/24/10 Physics 121 1 mA + B N hand A+ B 12 B A A NB B N hand A ( 1 aA = N hand mA 9/24/10 A + NB NA B A A ) Physics 121 1 aB = NA mB B 13 (mA + mB )a = N hand mA a = N hand mB a = N A A A + NB A B (mA + mB )a = N hand 9/24/10 Why is this N “on A” and not “on A+B”? A Physics 121 + NB A + NA B 14 NB A + NA B =0 or NB 9/24/10 A = NA Physics 121 B 15 FA 9/24/10 B = FB Physics 121 A 16 It will work for every case until we get into systems where more than two-bodies interact at the same time– for example when radiation (e.g., light) is emitted. 9/24/10 Physics 121 17 “Net force “ = vector sum of all the forces acting on the object. F net a= m FA 9/24/10 Physics 121 B = FB A 18 ...
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## This note was uploaded on 12/28/2011 for the course PHYSICS 121 taught by Professor Shawhan during the Spring '10 term at Maryland.

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