Does anyone out there have a few minutes to review a problem I worked out ?(adsbygoogle = window.adsbygoogle || []).push({});

I need to know where I am making errors and how to correct them

If you have a few minuted and are willing to help a fella out please reply ASAP

Here goes The problem states to find the following

1. Acceleration 5. Work

2. mass 6.the weight of three rayovac cells placed on the object

3. Force 7. momentum with and without cells

4. KE 8. Impulse upon collision

Trial 1 weight of object = 985.5 g .986 kg

Xi = 100cm ti = 0

Xf = 38cm tf = 4sec

I need velocity for accelartion v = d/ t = -.62 m/4s = -0.155 m/s

a = v / t = (0.155 m/s) / 4 s = -0.039 m/s^2

mass = w / g = 0.986kg / (9.8 m/s^2) = 0.101kg (why is ans. not in newtons)

Force F = m x a =0.101kg x (-0.039 m/s^2) = - 2.59 N

KE = (1/2) m x v^2 = (1/2)(0.101kg)(-0.155 m/s)^2 = -0.024 J, (can J be -)

work W = (F cos 0) X = ? I am stuck here, the object is on a level surface I am thinking that (cos 90) is correct am I right ?

PLease any help will be appreciated I am trying to complete assignment and study for test.

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# Homework Help: Not hard If you know how (homework) I don't

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