Recent content by hndalama

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    Find vertical distance of missed shot

    it can't be negative, the question is asking for the "distance" which is a scalar quantity. And the question is actually a multiple choice question: The given options are: a. 0.43 m b. 0.53 m c. 0.63 m d. 0.73 m e. 1.50 m I picked 0.73 but that was marked wrong
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    Find vertical distance of missed shot

    actually guys, I tried it again and the answer I'm getting is still marked wrong. the angle(b) of the blowgun is sinb=4/10 b =23.58 in x direction u = 25cosb =22.9 a=0 s=10cosb =9.17 so t=9.17/22.9 = 0.4 in y direction t = 0.40 a=-9.8 u= 25sinb = 10 s=ut +0.5at^2 s= 3.216 vertical distance...
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    How to find previous threads I have started?

    How do I find the threads that I previously started?
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    2D kinematic problem: Tennis serve

    The question is asking us to solve for θ. First I would convert the velocity 170km/h to m/s, then resolve this into its horizontal and vertical components. They will be in terms of θ. Then use kinematic equations and the given information to derive an equation in terms of θ. Then the plan is to...
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    2D kinematic problem: Tennis serve

    how did you get t=0.534s? as far as I can tell, time is unknown? you need to convert 170km/h into m/s. from step 1, it looks like you've made the assumption that vfy=0, but there is no reason to think that the ball would have 0 velocity by the time it got to the net or floor. Did you post a...
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    Find vertical distance of missed shot

    ah ..ofcourse. Thank you:wink:
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    Can this gravity problem be solved without using the Earth's mass

    Homework Statement A satellite orbits the Earth in a geosynchronous orbit around the equator, meaning that its period is 24 hours and it stays above the same location on Earth at all times. (G = 6.67 x 10⁻¹¹ Nm²/kg².) What is the radius of its orbit? Homework Equations GM/r2 = v2/r = w2r...
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    Find vertical distance of missed shot

    Homework Statement A hunter is aiming a blowgun directly at a bird on a tree branch 4.0 m above the blowgun and 10 m away. If the speed of the dart is 25.0 m/s and the bird stays in place, by what vertical distance will the dart miss the bird? Homework Equations s= ut + 0.5at2 The Attempt at...
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    Angular acceleration of an atwood pulley

    T1 - 10g = 10(-A) T1 =10g - 10A A = ar = 0.25a T1 =10g - 2.5a T2 - 6g = 6A T2 = 6g + 6A T2 = 6g + 1.5a T1 (0.25) - T2(0.25) = Ia (2.5g - 0.625a) - (1.5g + 0.375a) = Ia g = 1.313a a = 7.46 I think that's right. Please let me know if it isn't. I thank you for your help.
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    Angular acceleration of an atwood pulley

    How could the tension on either side of the rope not be equal? My understanding is that one property of tension is that it is always equal throughout the length of a rope. another question is if the pulley is frictionless then how could tension in the rope rotate the pulley?
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    Angular acceleration of an atwood pulley

    I think I'm quite lost on this. I don't understand how the masses could have moments of inertia when they are not rotating. One mass will move straight down and the other will move straight up. How do I find the tension in the rope? I know that tension along a rope is the same throughout the...
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    Angular acceleration of an atwood pulley

    Homework Statement An Atwood machine is a rope that passes over a pulley with a block attached to each end of the rope so that the blocks are not in contact with the floor. The frictionless axle of the pulley is oriented horizontally, and the rope is vertical save where it makes contact with...
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    Force diagram of a spinning mass tied to a string

    this only applies if the mechanical/overall energy is conserved. the point I and I think @CWatters are making is that it isn't in this problem. The calculation I made was to show that mechanical energy is lost. rather than the question being wrong can't we conclude that the loss of energy is due...
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    Force diagram of a spinning mass tied to a string

    To find the difference in energy don't we have to account for the kinetic energy as well. so shouldn't it be KE(bottom) - KE(top) - PE(top) . PE at the bottom is 0. so using CWatters numbers the change in energy is 36.9J -13.7J - 45.9J = -22.7 J But how does considering the change in energy...
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