2O1O APC
PHYSICS B FREE-RESPONSE OT'ESTIONS (FOrM B)
F_0.020 m_---l
ml
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m2
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by a 0.020 m length of insulating string as
Two small objects, each with a chafge of '*
shown in the diagram above. The q[i_ects are in)-tially at rest on a horizontal, nonconductins frictionless surfag
TheeffectoforavitvoneachobiecMrebtheotherisneclieible.|r:-.t\ir..,i\"Y4.
(b) Illustrate the electric field by drawing electric field lines for the two objects on the following diagram..
+ry
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'H-,*.*,
,,(iF
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The masses of the objects are
1W*^^"
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ml = 0.030 kg and mz = 0.060kg. The string is now
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cut.
d '
i(c),/Calculate the magnitude of the initial acceleration of each object'
(d) On
v
the axes below, qualitatively sketch a graph of the acceleration a of the object of mass m2 versus the
distance d between the objects
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o.=\,2*i6r*lt' I \
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rrnz:3'ioet0-=-Obq r2l i
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happens to the speeds of the objects as time increases, assuming that the objects
remain on the horizontal, nonconducting frictionless surface.
(e) Describe qualitatively what
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