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Physics 101 Problems, need help. I'm dumb.

  1. Nov 20, 2005 #1
    I would really appreciate it if someone could help me find a solution to these problems. It's Physics 101.

    An engineer must design a curved exit ramp for a highway in such a way that a car, exiting at the posted speed limit of 13.41 m/s (30 mi/hr), does not depend on friction to round the curve without skidding. The radius of the curve is 153.0 m. At what angle with respect to the horizontal must the curve be banked (in degrees)?

    Find the speed of a satellite in a circular orbit around the earth with a radius 4.31 times the mean radius of the earth; RE 6.37E+3km; ME 5.98E+24kg.

    The small spherical planet called "Glob" has a mass of 6.80×1018 kg and a radius of 6.50×104 m. A 48.0 kg satellite is in a circular orbit around the planet Glob at a height of 1.20×105 m above the planet's surface. Calculate the speed of the satellite.

    A satellite is in a circular orbit around the earth. The period of the satellite is 27.1 hr. Calculate the radius of the orbit of the satellite. Data: Mass of the earth = 5.98 e+24 kg. What is the speed of the satellite?
  2. jcsd
  3. Nov 21, 2005 #2


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    It would be nice if you would show some of your work or atleast understanding. There are alot of questions there. I will in genorosity address your first question (despite the lack of work shown).

    The concepts you should apply are that of circular motion, specifically the force needed to keep an object in motion is F = mv^2/r. Now usually this force comes from friction on the road for a car, but if we add an incline to the curve, we can instead use gravity to help. You must find the incline such that the force of gravity acting along the centripetal acceleration is equal to the centripetal force.
  4. Nov 25, 2005 #3


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    Hi ConsoleMaster, welcome to Physics Forums. If you have looked around, you will notice we have a lot of good discussions about not only homework questions but all manner of topics. It is true, in order for us to assist people with homework, you need to show what you have tried and where you are getting stuck. There are many here who are willing to help steer you in a successful direction. Once again, welcome to our PF community.. :smile:
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