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Shadow236
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Homework Statement
A 9 kg object is subjected to two forces, [PLAIN]http://www.webassign.net/images/Farrowbolditalic.gif1 = 7 N i - 4 N j and [PLAIN]http://www.webassign.net/images/Farrowbolditalic.gif2 = 7 N i - 9 N j. The object is at rest at the origin at time t = 0.
(a) What is the object's acceleration?
(b) What is its velocity at time t = 14 s?
(c) Where is the object at time t = 14 s?
(All answers in unit vector notation)
Homework Equations
(a) Fnet=ma
(b) V = V0 + at
(c) X = X0 + V0t + 1/2at2
The Attempt at a Solution
(a) Fnet = F1 + F2 = 14i - 13j
Fnet = ma -> a = (14i-13j)/9
a = 1.56i - 1.44j (MARKED INCORRECT)
Why is this incorrect? If a = F/m then all I should have to do is add up the forces to get Fnet.
(b and c) I've used the equations above and got the answers wrong. Overall, I won't be able to get these answers correct unless I get the correct acceleration.
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