This print-out should have 20 questions.

Multiple-choice questions may continue on the next column or page – ﬁnd all choices before answering.

001 (part 1 of 2) 10.0 points

An object with a charge 3 C and a mass

0.4 kg accelerates from rest to a speed of

19 m/s.

Calculate the kinetic energy gained.

Answer in units of J.

002 (part 2 of 2) 10.0 points

Through how large a potential diﬀerence did the object fall?

Answer in units of V.

003 (part 1 of 2) 10.0 points

Consider three charges arranged as shown.

7 µC

1.8 µC

+

+

4 cm

−1 µC

−

2.4 cm

What is the magnitude of the electric ﬁeld strength at a point 1.7 cm to the left of the middle charge? The value of the Coulomb constant is 8.98755 × 109 N · m2 /C2 .

Answer in units of N/C.

004 (part 2 of 2) 10.0 points

What is the magnitude of the force on a −1 µC charge placed at this point?

Answer in units of N.

005 10.0 points

Would you feel any electrical eﬀects if you were inside the charged sphere of a van de

Graaﬀ generator? Why or why not?

1. None of these

2. Yes; the electric ﬁeld exists both inside and outside of the generator.

3. More information is needed.

1

4. Yes; the electric ﬁeld is very strong inside the van de Graﬀ generator.

5. No; although there are charges inside the generator, the net charge is zero.

6. No; the inside of the generator has zero charge and thus no electric ﬁeld.

006 10.0 points

How many 105 W lightbulbs can you use in a

110 V circuit without tripping a 15 A circuit breaker? (The bulbs are connected in parallel, which means that the potential diﬀerence across each lightbulb is 110 V.)

Answer in units of bulbs.

007 (part 1 of 3) 10.0 points

The energy (in Joules) stored in a capacitor with capacitance C (in Farads), having a potential diﬀerence V (in volts), is given

1

by W = C V 2 . One application is in the

2

electronic photoﬂash or strobe light.