Recent content by racecar12

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    Block Jump from Ramp: Find Speed v

    Oh man, you are correct. I made an algebra mistake while moving everything over to solve for v. Good catch. And thanks a bunch!
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    Distance traveled using velocity

    Hey physics problems can be tough to get thru sometimes. You can use an equation that relates velocity, time, and distance to get your answer. Remember, Average velocity = Δx divided by Δt...where x is displacement and t is time. The trick here is also that you have two people moving at the...
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    Block Jump from Ramp: Find Speed v

    Hey, thanks for your constructive contribution to my inquiry. I attempted the solution in the way you suggested. I get v to equal 6.3228, which is unfortunately not the correct answer. I'm wondering if I may have to consider the total length the object travels...like adding Δy to the...
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    Block Jump from Ramp: Find Speed v

    Yes, you are correct that kinetic energy equals 0.5mv2. However, removing d from the equation takes me much farther from the answer, which I know to be 5.95617m/s. if I proceed with the way that I have thought, I get v to equal 5.96046. Close, but no cigar. I am making a mistake somewhere...
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    Block Jump from Ramp: Find Speed v

    Thanks for looking at this post. Here was my though process as I approached this problem... We'll just use the conservation of energy theorm for this problem. Einitial=Efinal Kinitial+Uinitial=Kfinal+Ufinal Since the massive object has no initial kinetic energy at the start of the system...
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    Block Jump from Ramp: Find Speed v

    Homework Statement A block starts at rest and slides down a frictionless track except for a small rough area on a horizontal section of the track It leaves the track horizontally, flies through the air, and subsequently strikes the ground. The acceleration of gravity is 9.8 m/s2 . What is...
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    Downward acceleration in an elevator

    I clearly don't understand a lot about physics, forces, etc. If I'm understanding correctly, Fnet = N-W Is Fnet supposed to equal zero? I understand that W is equal to mg. the force of W then is -8.82kN. Is that right? I mean do I account for the downward direction of gravity in this...
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    Downward acceleration in an elevator

    I tried it again... There are 2forces acting in this problem. One is the weight force pushing down, which is W=mg. The second force is the normal force pushing up from the floor of the elevator, N=ma. W=mg m=0.9kN g= -9.8 W=-8.82N N=ma m=0.9kN a=-1 N=-0.9N Since the elevator...
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    Downward acceleration in an elevator

    Homework Statement Person weighing 0.9kN rides in an elevator that has downward acceleration of 1m/s^2. What is the magnitude of the force of the elevator floor on the person. Answer in units of kN. Homework Equations F=ma The Attempt at a Solution I drew a force body diagram...
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    Person pushes down the length of the handle of a 12.1kg

    Did what you said... Fx = 9.4 Fy = 9.1 F = 13.1N Thank you
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    Person pushes down the length of the handle of a 12.1kg

    Thanks for the clarification about gravity :) I went back to find the y component of the vector...to equal 1.33sin41? I thought 9.4 was the x component of the Force. Does 1.33sin41 equal the y comonent of velocity? If so, then I could go about finiding the y component of acceleration and...
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    Person pushes down the length of the handle of a 12.1kg

    To find Fy, I used the mass of the object x the negative acceleration due to gravity. F= 12.1(-9.8) I'm missing the normal force, I think? But now, I am unsure how to calculate it
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    Person pushes down the length of the handle of a 12.1kg

    Homework Statement Person pushes down the length of the handle of a 12.1kg lawn spreader. The handle makes an angle 44.1 degrees with the horizontal. Person wishes to accelerate the spreader from rest to 1.33m/s in 1.7s. What forece must person apply to the handle?Homework Equations F=ma...
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    What is the velocity of a ball thrown from a building before it hits the ground?

    Oh yay we got the same answer :) Thanks a ton. I'm not very good at these types of problems yet...but I will keep practicing.
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