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    Mini-project help please

    Our teacher supplied us with one 8.5x11 sheet of paper, 2 paper clips and 12in of masking tape. What we have to do is put this stuff together and release it from about 9 feet above the ground. I has to stay in the air for 8 seconds or more and land inside a box on the floor (which means it...
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    Precal - Rotation of a Conic

    Ok. So i got that part where you replace x with x'cos(theta)+y'sin(theta) and y with -x'sin(theta)+y'cos(theta). My book shows us the proof for this using matrices. What my teacher wants us to do its prove this using polar equations or something like that. I started out with the drawing...
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    Help please, motion of charged particle in mag field

    A proton moves in a circular orbit perpendicular to a uniform magnetic field of 0.758T. Find the time it takes the proton to make one pass around the orbit. Just need someone to help me start off. All I have is that the B=0.758T, q=1.6x10^-19C and m=1.67x10^-27kg. What formulas do I need...
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    Electric field question

    A proton accelerates from rest in a unifor electric field of 640 N/C. At some later time, its speed is 1.20X10^6m/s. Find the magnitude of the acceleration of the proton. Hmm.. not sure what formula to use on this one.. can someone help?
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    Help please thermal expansion

    The band below is stainless steel (coefficient of linear expansion=17.3X10^-6 degrees C, youngs modulus=18X10^10 N/m^2). It is essentially circular with an intial mean radius of 5.0mm, a height of 4.0mm and a thickness of 0.50mm. If the band just fits snugly over the tooth when heated to a...
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    Need help w/ centripetal acceleration lab questions

    These questions are from a lab we just did. 1. Why is an unbalanced force required to produce circular motion? 2. The ratio of squared velocity to radius is a constant. In other words, the centripetal acceleration did not change as the radius changed. Explain. 3. In an amusement park...
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    Conceptual question

    An engineer wishes to design a curved exit ramp for a toll road in such a way that a car will not have to rely on friction to round the curve without skidding. He does so by banking the road in such a way that the necessary force causing the centripetal acceleration will be supplied by the...
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    Finding angular acceleration for this prob

    A rotating wheel requires 3.00s to rotate 37.0 revolutions. Its angular velocity at the end of the 3.00-s interval is 98.0rad/s. What is the constant angular acceleration of the wheel? What i did was i used average w=delta(theta)/delta time. Then i used average w=radical(w^2+wo^2) to find...
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    Average force problem

    A 3.0kg steel ball strikes a massive wall at 10m/s at an angle of 60degrees with the plane of thge wall. It bounces off with the same speed and angle. If the ball is in contact with the wall for .20s, wut is the average force exerted on the ball by the wall? its is wut i got.. p=mv p=mv...
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    Need help with hw momentum and collisions

    i hav no clue how to do this problem... How fast can you set the Earth moving? In particular, when you jump straight up as high as you can, you give the Earth a maximum recoil speed of what order of magnitude? Visualize the Earth as a perfectly solid object. In your solution state the...
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    Need help with work and energy

    Two blocks, A(50kg) and B(100kg) are connected to a string. The pulley is frictionless and of negligible mass. The coefficient of kinetic friction between block A and the incline is Mk =0.25. Determine the change in the kinetic energy of block A as it moves from C to D, a distance of 20m up...
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    Help with force of friction

    masses m1=4.00kg and m2=9.00kg are connected by a light string tht passes over a frictionless pully. m1 is held at rest on the floor and m2 rests on a fixed incline of 40.0degrees. the masses are released from rest, and m2 slides 1.00m down the incline in 4.00seconds. determine the acceleration...
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    Help with projectile motion

    hi im new to the board.. my class recently did a lab using water rockets as projections. Our rocket went 30.2m in 1.73 seconds. can u guys help me find Vo, V, angle of launch and angle of impact? i need help on this a lot. can u guys also show me the steps in doin this. thanks