Download Current Electricity Homework (NAT5)

Current Electricity Homework (NAT5)
1. A battery pushes 120C of charge through a circuit in 2
minutes. What is the size of the electric current in
amps? (2)
2. The following passage is taken from NASA research into
lightning:
“Lightning is the effect of static electricity build-up within a thunderstorm cloud
system. It is a giant electrical spark that can have a peak current flow greater
that 200,000 amperes during a period of a few microseconds. Thunder results
from the sudden heating of the air to about 20,000°C by the flow of current
along a narrow channel. This flow can be from cloud to ground with several
individual strokes separated by a tenth of a second. Or it can be from cloud to
cloud strokes which illuminate the cloud. Strokes can also be from cloud
through an aircraft or aerospace vehicle operating in the vicinity.”
(http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19990009077_1998432277.pdf)
a) How much charge would flow if a lightning bolt carrying a current of 200,000
amps travelled from cloud to ground in 0.1 seconds.
(2)
b) If the cloud to ground distance was 15km and the time for the lightning bolt
to reach the ground was 0.1s, calculate the speed of the lightning bolt.
3.
A single cell has a voltage of 1.5V State clearly what this means.
(2)
(2)
4. Read the following 2 statements:

Voltage is a measure of the energy delivered to each
coulomb of charge.

Current is a measure of the number of coulombs flowing per
second.
A 9V battery delivers a current of 3A to a lamp. How much energy
is delivered to the lamp every second?
(2)
(10 marks)