Recent content by euphtone06

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    Speed aircraft carrier based on reflected pulse frequency

    I tried working it out again but I am not sure if its right. n ' = n [v - vo] / [v - vs] c>>>carrier, b>>submarine all v (sound), v0(observer), vs (source) are moving in + x direction when submarine is source: carrier observer (reflecting) n ' = 2400 [1500 - vc] / [1500 - vb] n ' =...
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    Speed aircraft carrier based on reflected pulse frequency

    Homework Statement Submarine is traveling at 12 m/s toward an aircraft carrier emits a 2400 Hz sonar pulse. The reflected pulse returns with a frequency 2310 Hz. What is the speed of the aircraft carrier? (Positive/negative means the carrier is moving toward/away from the submarine.) The...
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    Train whistle frequency difference in approaching and receding

    Sorry I am still confused at what which frequency should be inputed in my equation 595/(340 + 29) 595(340 - 29) just 595? or the average of those?
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    Train whistle frequency difference in approaching and receding

    Homework Statement Whistle frequency is 595 Hz for the train and sounds higher or lower depending on whether it approaches it or recedes. Calculate the difference in frequency between approaching and receding train whistle for a train moving at a speed of 105 km/h. Speed of sound is 340 m/s...
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    What is the Angular Acceleration of a Rod?

    Do you have to account for the total mass of the system? .5*4.915*(4+4?)*9.8*cos31/235.697= .7 rad/s^2
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    What is the Angular Acceleration of a Rod?

    Homework Statement http://img505.imageshack.us/img505/6741/rodprobbw3.gif" Homework Equations Itot= 1/3MrL^2 + 2/5 MsR^2 + Ms(L + R)^2 = 235.69784 Cm= (Mr(L/2) + Ms(L+r))/(Mr+Ms) = 4.915 angular accel = Torque/Itot Torque= 1/2Lmgcos(theta) The Attempt at a Solution I solved for...
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    What is the force exerted by a football on a kicker's foot?

    It was just the negative sign! Thanks guys I was killing myself over this
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    What is the force exerted by a football on a kicker's foot?

    Following your advice and retrying everything I still come up with the same answer that the Force = m ΔV/t
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    What is the force exerted by a football on a kicker's foot?

    so would it be, impulse = force x time 1264.16667 N / .012 s = ans?
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    What is the force exerted by a football on a kicker's foot?

    Homework Statement A barefoot field-goal kicker imparts a speed of 37 m/s to a football initially at rest. If the football has a mass of 0.41 kg and the time of contact with the ball is 0.012 s, what is the force exerted by the ball on the kicker’s foot? Answer in units of N.Homework Equations...
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    Finding a landing speed from spring constants

    Im completely lost. The weight on springs is 13880 N and uncompressed length is 2.4 compressed is still 1.2 which is stated in the problem.
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    Finding a landing speed from spring constants

    .4 m? (7750*1.790967742)/ (3 * 11566.7 ) = .3999988473
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    Finding a landing speed from spring constants

    How do I apply the weight to the equation?
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    Finding a landing speed from spring constants

    And how might I find this additional energy and apply it to the problem at hand?
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    Finding a landing speed from spring constants

    Homework Statement Problem: http://img147.imageshack.us/img147/8509/physjc9.gif Additional info: mass of the lander 7750 kg, 1.790967742 is the mag of acceleration due to gravity, this info was found in earlier parts of the problem Homework Equations I used these 2 equations and...