Recent content by ownedbyphysics

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    Simple vector physics-please help!

    Simple vector physics--please help! I'm having a little trouble with this physics problem. It seems so simple but I am stumped. A river flows with a uniform velocity v. A person in a motorboat travels 0.942 km up- stream, at which time a log is seen floating by. The person continues to...
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    What is the theoretical minimum force

    a 82.500 kg student, starts from rest. A constant force acts on him for 37.5m to give him a speed of 97.5 m/s. Use the Work- energy theorem to find the magnitude of the force. this is my equation which I'm unsure about 1. f*s= .5mv^2f - .5mv^2i 2. f= .5(82.5)(97.5^2)/37.5 I just want to...
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    Another conservation of momentum

    The issue of the New York Times had a mass of 5.4 kg. Suppose a skateboarder picks up a copy of this issue to have a look at the comic pages while rolling backward on the sakteboard. Upon realizing that the New York Times doesn't have a "funnies" section, the skateboarder promptly throws the...
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    Conservation of momentum problems

    The larges grand piano in the world is really grand. Built in London, it has a mass of 1250 kg. Suppose a pianist finishes playing this piano and pushes herself from the piano so that she rolls backwards with a speed of 1.4m/s. Meanwhile, the piano rolls forward so that in 4.0s it travels 24 cm...
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    Find the friction force impeding its motion.

    my teacher doesn't teach us anything either...except this ma=mgsin(theta)-umgcos(theta) then you can use that to solve for coefficient of kinetic friction and friction force. I think.
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    Tension in the coupling between the locomotive and the first car

    My teacher told us that "the force of friction on an inclined plane is always going uphill and is always UmgcosO," but he didn't say if that was just in the case of an object going downhill. When an object is going uphill, is the force of friction against the object or still uphill. If it is...
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    Tension in the coupling between the locomotive and the first car

    would the train be pulling itself and the coupling? and the coupling pulling itself and the other coupling?
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    Tension in the coupling between the locomotive and the first car

    A 97 250kg train pulls two freight cars. The first car has a mass of 51 355 kg and the second has a mass of 18 400 kg. The whole train accelerates at .01750m/s^2. What is the tension in the coupling between the locomotive and the first car? A. I used Ft=ma and took (51355)(.1750)= 8987.1 N...
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    Heart/cardiovascular problems at 21?

    I've read that many diseased hearts have low Coenzyme Q-10 levels, you should check that out. Also, if you're taking statin drugs for BP, you might want to supplement with Coenzyme Q10 because studies have been found that those drugs decrease levels by 40% (and Q10 levels start declining after...
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    Can people really use yogic powers/their mind to levitate?

    one of my teachers claimed to have seen Muhammad Ali levitate O-O
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    Why more matter than antimatter

    If there is duality, at the big bang, when matter and antimatter was created, why did the balance shift to matter? Someone told me that there is a theory that the particles that have no charge was left over and created matter?
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    Help with problems over Newton's Laws

    That's the part I don't understand because Fn= mg....I don't know how to find the normal force without just using 110.0*9.81
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    Help with problems over Newton's Laws

    or maybe I have to find the net acceleration since I found the acceleration acting up so would I do 9.81- .4745 =9.3355 then multiply it by the mass to get the weight? = 1026.905 N? would the scale be reading newtons?