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    Distance and time

    i need some help with this: the distance d that a certain particle moves may be calculated from the expression d=at+bt^2, where a and b are constants; and T is the elapsed time. complete the following statement: the dimensions of the quantities a and b are..., respectively help please i...
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    Gravity help

    can someone provide me the formulas i can't seem to find any of them in this forum?
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    Gravity help

    o really? thats the right answer but can u teach me how to do it mathematically? because i have to show my work and steps in how to get the answer
  4. E

    Gravity help

    it'll go six times higher?
  5. E

    Gravity help

    is it 96.04m?
  6. E

    Gravity help

    yes but i don't have the formulas or the textbook with me but only the questions because this is homework over the summer
  7. E

    Gravity help

    how do you calculate to get the height?
  8. E

    Gravity help

    If an object is thrown vertically upward on the moon how many times higher will it go than it would on earth if they both have the same initial vel. Acceleration on moon is 1/6 of what it is on earth I need some help on solving this. Thank You
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    Converting mph

    is this correct?
  10. E

    Converting mph

    when i convert 65 mph into ft/s is it 95.33 ft/s and and when converting 65mph into km/h is it 104.60736 km/h?
  11. E

    Converting mph

    i need some help on a problem... does anyone know how to convert 65mph into ft/s and km/h? i would appreciate it THANKS! =)
  12. E

    Force and Work

    thanks for the help cyrusabdollahi! Appreciate it!:smile:
  13. E

    Force and Work

    hi i need help on two of my homework problems one on work and the other on force As you walk, there is a static frictional force between your shoes and the ground. Is any work done? Explain your answer. If three objects exert forces on a body, can they all do work at the same time? Explain...
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    Simple Think Critically and Explain Question

    Thanks a lot guys for the help:smile:
  15. E

    A Couple More Simple Think critically and Explain Questions

    oh sorry about that, but i did try to do them myself but i didn't understand them so i decided to skip them move on and then go back to try to figure out the answers for these few problems but i couldn't so I decided to post them up as well
  16. E

    A Couple More Simple Think critically and Explain Questions

    Think and Explain 1. Why is it important that the resistance of an extension cord be small when it is used to power an electric heater? 2. Will the current on a light bulb connected to 220V be more or less than when the same light bulb is connected to 110V? How much? 3. In 60- Hz...
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    Simple Think Critically and Explain Question

    Think and Explain Is this label on a household product cause for concern? "Caution: This product contains tiny electrically charged particles moving at the speeds of 10000000 km per hour" can someone please help me with this problem I would appreciate it Thanks!!:smile:
  18. E

    Simple dB question

    hi, I'm having trouble with a question and i was wondering if anyone can help me out. "To a person who is hard of hearing, normal conversation (60dB) sounds like a soft whisper. What increase in sound levels (in dB) must a hearing aid provide? How many times must the sound wave pressure be...
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    Simple echo question

    i need help on the following problem: "carol drops a stone into a mine shaft 122.5 m deep. How soon after she drops the stone does she hear it hit the bottom of the shaft?" i know that the acceleration is 9.8m/s^2 but i can't use it as speed in the speed=distance/time equation please help me...
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    DB question

    hi, i need help in understanding something on sound. if admam works near a jet plane that is taking off and experiences the sound level of 150dB. then the protectors to reduce the sould level to that of a chain saw, what decrease in dB is needed? i think it's 40 but i am not sure. and also if...
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    Speed for lightning and thunder

    i still don't understand. is it that for speed *time = distance. that for the speed of sound is approx. 340m/s so when you divide 1000m by 340m/s you get about 3. therefore you need to divide by 3 to get the distance. am i off track?
  22. E

    Physics concept

    hi my math teacher ask us this the other day..."in the military, as marching soldiers approach a bridge, the command route step is given. the soldiers then walk out of step with each other as they cross the bridge. explain." i don't understand what she means at all. is it even a physics concept...
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    Simple question but still can't figure it outsound

    o thanks for the speed of sound. so all i have to do is plug it in, but then remember to divide by 2 for the distance to get 34 m.?
  24. E

    Speed for lightning and thunder

    i don't understand how you can estimate how far the lightning flash is from you by counting the seconds betw the flash and thunder, then divide by three to result in the distance in kilometers. can someone please explain where does the logic that resulted in this rule? i don't understand why it...
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    Simple question but still can't figure it outsound

    i am having trouble with this question" if you clap your hands the echo from a distant wall 0.20s later, how far away is the wall?" how do you do this without the speed given to substitute into the speed= distance/time equation?
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    Simple force question

    Thanks A Bunch!!
  27. E

    Simple acceleration problem

    HI!! i need help on this problem..... A 60kg and a 40kg girl uses an elastic rope while engaged in a tug a war on the icy frictionless surface. If the acceleration of the girl towards the boy is 3.0m/s/s, determine the magnitude of acceleration of the boy to the girl. Please help if you...
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    Simple force question

    hi this is my first year in physics and i am already confused on it. I really need help on the following question: "The force of -9000 N is used to stop a 1500 kg car traveling at 30 m/s. What is the breaking distance is needed to bring the car to a halt?" I have no idea which formula to use or...
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