Recent content by buttterfly41

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    Calculating Potential Difference for Electron Acceleration

    electricity problem :( so here's the problem: through what potential difference would an electron need to be accelerated for it to achieve a speed of 42.0% of the speed of light, starting from rest? The speed of light is c = 3.00e8 m/s so i thought the equation i would use would be...
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    Vector problem with electricity

    vector problem with electricity :( Ok, so i am having problems with my vectors in two homework problems (or maybe i went wrong some where else)... #1) Four identical point charges (q = +10.0 µC) are located on the corners of a rectangle. The dimensions of the rectangle are L = 70.0 cm and W...
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    Prisim and angle of deviation problem

    Light of wavelength 700 nm is incident on the face of a fused quartz prism at an angle of 77.0° (with respect to the normal to the surface). The apex angle of the prism is 60.0°. n=1.459. a) the angle of refraction at the first surface (b) the angle of incidence at the second surface (c)...
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    How Do You Calculate Work and Internal Energy in Thermodynamics?

    thanks to both of you, i was confused, but i get it now! THANKS1!
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    How Do You Calculate Work and Internal Energy in Thermodynamics?

    1. A gas is compressed from 10.00 L to 2.00 L at a constant pressure of 0.800 atm. In the process, 400 J of energy leaves the gas by heat. (a) What is the work done by the gas? (b) What is the change in its internal energy? so for part a, i have tried: P*deltaV=W 8.106E4 * 8 =...
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    Calculating Train Whistle Frequency with a Moving Observer: Physics Problem Help

    ok, so this is what i did, F(beat)=4.6Hz V(train)=8.60m/s V=343m/s f' = trains whistle f(beat)=f1-f2 f1=(f'*V)/(V+V(train) and f2=(f'*V)/(V-V(Train)) and putting it all togther i got: f(beat)=[(f'*V)/(V+V(train)] - [(f'*V)/(V-V(Train))] 4.6=abs[343f'/(343+8.6)]-[343f'/343-8.6)]...
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    Calculating Train Whistle Frequency with a Moving Observer: Physics Problem Help

    i need help with waves :( please the problem is: While Jane waits on a railroad platform, she observes two trains approaching from the same direction at equal speeds of 8.60 m/s. Both trains are blowing their whistles (which have the same frequency), and one train is some distance behind the...
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    Can Sound Travel Fast Enough to Warn a Man of a Falling Flower Pot?

    thank you very much... i fixed both of my problems with your adivce... because for both of them i put in one wrong number for a coefficient... so again, thank you for you help ;0 Jenni
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    Can Sound Travel Fast Enough to Warn a Man of a Falling Flower Pot?

    A flower pot is knocked off a balcony 21.6 m above the sidewalk and falls toward an unsuspecting 1.79 m-tall man who is standing below. How close to the sidewalk can the flower pot fall before it is too late for a shouted warning from the balcony to reach the man in time? Assume that the man...
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