Recent content by Nubcake

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    High School Understanding Work Done and the Role of Force in Solving Problems | 360J Example

    I was more concerned about the direction and the force ; doesn't the weight of the barrel act in the opposite direction of movement?
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    High School Understanding Work Done and the Role of Force in Solving Problems | 360J Example

    I have always managed to solve problem asking how much work is being done but then once I start to think about the work being done I get confused. E.g A barrel of weight 200N is raised by a vertical distance of 1.8m by being moved along a ramp. The work done here would be 200 x 1.8 =360J . I do...
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    Calculate 5Σ r=0 r(r+1): Find the Sum!

    Calculate 5 \Sigma r=0 r(r+1) (Sorry I don't know how to do the proper notation online) How do you calculate the sum for this since the common difference is changing? I tried to write them out separately so the sum of r x sum of r+1 but I don't know how you put that in the sum formula. Sn =...
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    Question: How does mass affect terminal velocity when a drag force is present?

    If two people of different masses say 50kg and 100kg were to suddenly jump off a building , why would the person with more mass attain a higher terminal velocity? I thought mass was irrelevant. I missed 1 lesson on this in class but this part I don't understand properly. If they were the same...
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    Find Sum of Arithmetic Series Sn: Σ 200 r=5 5r-2

    Find the sum of \Sigma 200 r=5 5r-2 Sn = n/2 [2a + (n-1)d ]I used S 200 and I got about 101400 but then when I verified on my calculator it was 100058, my calculator has the sigma notation for working out the sum of , how do you get 100058?
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    Calculating Stress Applied to Rubber Band: 1.0 MPa/ unit Strain

    Rubber has roughly a stress of 1.0 MPa per unit strain . how much stress has been applied to the rubber band? Stress = f/a though it was straight forward and used the formula for stress but when I looked at the answer it was 2.0 x 10^6 Pa But why?
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    Calculating the Mass of Earth's Atmosphere: What Assumptions Were Made?

    I guess I must have made a mistake with F = ma now that I think about it , I didn't rearrange the formula for mass .
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    Calculating the Mass of Earth's Atmosphere: What Assumptions Were Made?

    Well I used it and got a different answer to the right answer , instead of F = ma , W = mg is used.
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    Calculating the Mass of Earth's Atmosphere: What Assumptions Were Made?

    Why doesn't F = ma work in this situation ?
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    Calculating the Mass of Earth's Atmosphere: What Assumptions Were Made?

    1.Atmospheric pressure is 101kPa a) Calculate the total force exerted by the atmosphere on the surface of the Earth. Radius of Earth is 6.4 Mm b)Calculate the mass of the Earth's atmosphere , State any assumptions made. P = F/A ρ = m/v [\b] [b]a) Surface area of a sphere is...
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    SI Units for Pressure: N m^2 or N m^-2?

    Force applied per unit area perpendicular to a surface , ... so it's N m^-2?
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    SI Units for Pressure: N m^2 or N m^-2?

    Are the SI units for pressure N m^2 or is it N m^-2?
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    High School Why Did Felix Baumgartner Jump From 128,000 Feet Instead of Going Higher?

    I think he got a little higher than that about 800+ but he slowed down afterwards.
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    High School Why Did Felix Baumgartner Jump From 128,000 Feet Instead of Going Higher?

    Just saw it now , he didn't manage to break the world record i think because he deployed his parachute at 4 min 19 seconds.
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    Undergrad CPA Problem for Dummies: Understanding Activity Networks

    This is not really a h/w question but one thing I so not understand with this precedence table in critical path analysis , why would it needs two dummies?Activity. | Depends On A | - B | - C | A D | B E | B,C...