Download Chapter 22-23 Review

Chapter 22-23 Review
A positive ion has more
a. Electrons than neutrons
b. Electrons than protons
c. Protons than electrons
d. Protons than neutrons
e. Neutrons than protons
The electrical force between charges depends
on the charges
a. magnitude
b. Separation distance
c. Both of these
d. None of these
When a car is struck by lightening, the resulting
electric field inside the car is
a. Normally huge, but for a brief time
b. Normally huge for a time longer than
the lightning strike itself
c. Small enough to be safe for an occupant
inside
d. zero
The electric field inside the dome of a Van de
Graaff generator
a. Depends on the amount of charge the
outside of dome
b. Depends on the volume of the dome
c. Depends on the charge and the volume
of the dome
d. None of these
If you comb your hair and the comb becomes
positively charged, then your hair becomes
a. Positively charged
b. Negatively charged
c. Unchanged
Heat a copper wire and its electric resistance
a. Decreases
b. Remains unchanged
c. Increases
The primary source of electrons in an ordinary
electrical circuit is
a.
b.
c.
d.
A dry cell, wet cell, or battery
The back emf of motors
The power station generator
The electrical circuit
On some early automobiles both headlights went
out when one bulb burned out. The headlights
must have been connected in
a.
b.
c.
d.
parallel
series
perpendicular
haste
As more lamps are put into a series circuit, the
overall current in the power source
a. increases
b. decreases
c. Stays the same
calculations
Calculate how much current warms your feet
with electric socks that have a 90 Ω heating
element powered by a 9-volt battery.
𝑉
𝐼=
𝑅
9
𝐼=
90
𝐼 = .1 𝐴
calculations
Calculate the power of a hair dryer that operates
on 120 volts and draws a current of 10 amperes.
𝑃 = 𝐼𝑉
𝑃 = 10 120
𝑃 = 1200 𝑊
What is the resistance of a 120 W incandescent
lamp connected to a 120 V power supply?
𝑉
𝑉
𝐼=
𝑡ℎ𝑒𝑛 𝑅 =
𝑅
𝐼
We know voltage and power with will tell us
𝑃
current… 𝑃 = 𝐼𝑉 𝑡ℎ𝑒𝑛 𝐼 =
𝑉
120
𝐼=
=1𝐴
120
𝑉 120
𝑅= =
= 120 Ω
𝐼
1
Common instance of charging by induction
thunderstorms
Know …
• Definitions
• Calculations
• Drawing circuits