Recent content by luvsk8ing

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    Determining the Force Between Crates in Motion on a Concrete Floor

    :approve: okay i drew it that way 'cause that's what my prof does. hmmm, bad habit i guess. tsk tsk. so since F32 and F23 have different signs, that completely makes sense then! thank you really!
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    Determining the Force Between Crates in Motion on a Concrete Floor

    hey cool! erm...those negative signs came from the way i drew my free body diagram. i put space in between each crate. so concentrating on the 3rd crate, i have horizontal forces of f_k to the left and another leftward force of crate 3 acting on crate 2 (F23). this force of which should be...
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    Determining the Force Between Crates in Motion on a Concrete Floor

    hmm...worked on it some more, and I'm getting: F32 = -m3*a_x-f_k with f_k=(mu)_k * m3*g = -(20kg*0.473m/s^2)-(0.700*20kg*9.8m/s^2) = -147 N therefore, magnitude is 147 N -possibly :eek:
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    Determining the Force Between Crates in Motion on a Concrete Floor

    okies, i did not see that the question was actually asking for magnitude. woops. let's focus on crate 3. so i'd have to do the x component/y component situation. but, wouldn't the y component be zero? normal force minus m3*g? so then for the x component: F_x = F32-F23-f_k with F23 being...
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    Determining the Force Between Crates in Motion on a Concrete Floor

    if i wanted to consider the middle crate, sort of like i was originally trying, would: F32 = f_k + F12 + m2*a_x ---would that be right? :D
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    Determining the Force Between Crates in Motion on a Concrete Floor

    ooh, thanks :D i'm analyzing crate 3. so F32 = m3*a_x. Therefore, F32 = 20.0 kg * 0.473 m/s^2 = 9.46 N?
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    Determining the Force Between Crates in Motion on a Concrete Floor

    Homework Statement The figure shows 3 crates being pushed over a concrete floor by a horizontal force f of magnitude 440N. The masses of the crates are m1=30 kg, m2=10kg, and m3=20kg. The coefficient of kinetic friction between the floor and each of the crates is 0.7. what is the magnitude F32...
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    2 Forces problems (Halliday/Resnick/Walker, 7th Ed. book)

    Thank you Mindscrape. Yes the tension equation is from Newton's second law. I had to research the Galilean relativity...ermmm. I'll just ask my professor later. Thank you though!
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    2 Forces problems (Halliday/Resnick/Walker, 7th Ed. book)

    Homework Statement In chapter 5, problems 26: A provided figure shows an overhead view of a 0.0250 kg lemon half and two of the three horizontal forces that act on it as it is on a frictionless table. Force F_1 has a magnitude of 6.00 N and is at θ_1 = 30.0° (and, btw, is in quadrant II)...
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    Homework Problem: How to solve a projectile problem with given information?

    Hello. Homework Statement There is a link to the problem and its picture here: http://media.wiley.com/product_data/excerpt/19/04717580/0471758019-1.pdf It is # 46. Here is the problem as well: In Fig. 4-44, a ball is thrown up onto a roof, landing 4.00 s later at height h=20.0m...
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