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Homework Help: Physics Help for SAT II

  1. Apr 17, 2005 #1
    A proton charge of 1.6 x 10^-19 coulomb moves trhough a vacuum with a speed v of 1 x 10^6 meters per second. It passes through a uniform magnetic field as shown above. If the force exeted on the proton is 8 x 10^-15 newton, the magnitude of the magnetic force is most nearly.

    (A) 1.3 x 10^-27 T
    (B) 2 x 10^-11 T
    (C) 5 x 10^-10 T
    (D) 5 x 10^-2 T
    (E) 20 T

    A plane mirror can be used alone to form a
    (A) magnifed real image
    (B) diminished real image
    (C) magnified virtual image
    (D) diminished virtual image
    (E) virtual image neither magnified nor diminished

    The answer is E. Why?

    A proton of mass 1.7 x 10^-27 kg and speed of 3 x 10^7 meters per second is moving in a circle of radius 200 meters. Which of the following is the best estimate of the order of magnitude of the magnetic force needed to maintain this motion?
    (A) 10^-20 N
    (B) 10^-14 N
    (C) 10^-8 N
    (D) 10^-4 N
    (E) 10^0 N
    Can you tell me the formula?

    On the basis of the Bohr model, it can be predicited that the internal energy of a hydrogen atom will
    (A) increase when any frequency of light impinges on the atom
    (B) change by any amount as a result of collisions with other hydrogen atoms
    (C) change only as a result of the emssion of light
    (D) be restricted to certain discrete values
    (E) always be the same
    Explain how you got the answer?

    If thin metallic foila few atoms thick is bombarded by a narrow beam of alpha particles, it will be observed that
    (A) all particles pass through undeflected
    (B) none of the particles are deflected through more than 45 .
    (C) most particles are de flected through more than 45 .
    (D) occasional particles are deflected through 180 .
    (E) all paricles are defkected through 180 .

    Explain how you got the answer?

    Of the following observable phenomena, which can be explained by using the wave model of light, but not the particle model?
    (A) Energy is transmitted by a light beam
    (B) Pressure is exerted by a light beam
    (C) A region reciving light fromt two small coherent sources can have points of zero intensity of light.
    (D) All of the energy emitted by an atom as light can later be completely transffered to another atom.
    (E) Light incident on a plane reflecting surface at a given angle is reflected at the same angle.

    Explain how you got the answer?

    A 12 kg object initally has 24 joules of kinetic energy. How far will the object move against a net resisitng force of 6 N?
    (A) 2 m
    (B) 4 m
    (C) 12 m
    (D) 16 m
    (E) 24 m
    Explain how you got your answer?
    Last edited: Apr 17, 2005
  2. jcsd
  3. Apr 17, 2005 #2
    For that much work I'm gonna have to ask you to do some before I do it for you.
  4. Apr 17, 2005 #3


    User Avatar
    Gold Member

    You need to really figure out why. Go problem by problem and tell us what formulas you are going to use and such. I gotta say though at least the first one doesnt make sense at all. How can it be 2 and 3 only and also 1, 2, and 3??? How the hells that possible llol.
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