Klastoets 3 Classtest 3

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Klastoets 3 / Classtest 3
1. Die ladings en koordinate van twee gelaaide
deeltjies wat vas gehou word in die xy vlak is
q13.0 ?C, x13.5 cm, y10.5 cm en q2-4 ?C,
x2-2.0 cm, y21.5 cm. Bepaal die grootte en
rigting van die elektrostatiese krag op q2. The
charges and coordinates of two charged particles
held fixed in the xy plane are q13.0 ?C, x13.5
cm, y10.5 cm and q2-4 ?C, x2-2.0 cm, y21.5
cm. Find the magnitude and direction of the
electrostatic force on q2. (5)
Waar sal n derde lading q34.0 ?C geplaas moet
sodat die netto elektrostatiese krag op q2 nul
is? Where could you locate a third charge q34.0
?C such that the net electrostatic force on q2 is
zero? (4)
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2. Die figuur toon n lang, nie-geleidende
massalose staaf met lengte L wat roteer om sy
middel en gebalanseer word deur n gewig W op n
afstand x vanaf die linkerkant. Aan die linker
en regterkante is klein geleidende sfere met
ladings van q en 2q vas. n Afstand h onder
elkeen is vaste sfere met ladings Q. Bereken die
afstand x wanneer die staaf horisontaal en
gebalanseer is. The figure shows a long,
nonconducting, massless rod of length L, pivoted
at its center and balanced with a weight W at a
distance x form the left. At the left and right
ends of the rod are attached small conducting
spheres with charges q and 2q. A distance h
directly beneath each is a fixed sphere with
charge Q. Find the distance x when the rod is
horizontal and balanced. (4)
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Vir watter waarde van h sal daar geen netto
vertikale krag wees as die staaf horisontaal
gebalanseer is? For what value of h will there be
no vertical force when the rod is horizontally
balanced? (3)
3. Wat is die netto elektriese veld by punt P as
gevolg van die vier ladings? What is the
net electric field at point P due to the four
charges? (3)
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4. Twee lang, gelaaide, konsentriese silinders
het radiusse van 3.0 en 6.0 cm. Die lading per
eenheidslengte is 5.010-6 C/m op die binneste en
7.010-6 C/m op die buitenste silinder. Bepaal
die elektriese veld by r 4.0 cm. Two long,
charged, concentric cylinders have radii of 3.0
and 6.0 cm. The charge per unit length is
5.010-6 C/m on the inner and 7.010-6 C/m on
the outer cylinder. Find the electric field at
r4.0 cm. (3)
Bepaal die elektriese veld by r 8.0 cm. Find the
electric field at r8.0 cm (3)