Radio Shack TRS-80 User Manual page 60

EXERCISE
11-4: Here's
an
old chestnut that the
Computer
really eats up: Design, write
and
run a
program which
tells
how many
days
you
have to
work,
starting at a
penny
a day,
so
if
your
salary
doubles each
day
you
know
which day you
earn
at least
a million
dollars.
Include
columns which
show
each
day number,
its
daily rate,
and
the total
income
to-date.
Make
the
program
stop after printing
the
first
day your
daily rate
is
a million dollars or
more.
The
"Brute Force"
Method
(Subtitled:
Get
a
Bigger
Hammer)
Much
to
the consternation of
some
teachers, a great value
of
the
Computer
is
its
ability to
do
the tedious
work
involved in the
"cut and
try",
"hunt and peck" or other
less
respect-
able
methods of
finding
an answer
(or
attempting
to
prove the correctness of a theory,
theorem
or principle).
This
method
involves trying
a
mess
of possible solutions to see
if
one
fits,
or find the closest
one, or
establish
a trend.
Beyond
that,
it
can be a powerful
learning
tool
by providing gobs of data
in
chart or
graph form
(later)
which
would
simply take too
long
to
generate
by hand.
EXERCISE
11-5:
You
have
a
1000 foot
roll
of fencing wire
and want
to create a
rectangular
pasture.
Using
all
of the wire,
determine what length
and width dimensions
will
allow
you
to enclose
the
maximum
number of square
feet?
Use the brute force
method;
let
the
Computer
try
different values for
L
and
W
and
print
out the
Area fenced by each
pair
of
L
and W.
The
formula for area
is
Area = Length
times
Width
or
A
=
L *
W
EXERCISE
1
1-6:
EXTRA
CREDIT
PROBLEM FOR
"ELECTRONICS TYPES"
As
a furtner
example (more complex and tends
to
prove the point
better) try
this final
(optional)
assignment in this lesson. It
involves a
problem
confronted
by
every electricity
student
who
has studied sources
(batteries,
generators)
and
loads
(lights,
resistors).
It
is
the
MAXIMUM
D.C.
POWER TRANSFER THEOREM
which
states,
"Maximum
DC
power
is
delivered to
an
electrical
load
when
the resistance
of that load
is
equal
in value to
the
internal resistance
of the source."
And
then
the
arguments
begin
. . .
"Use
a
high
resistance
load because
it
will
drop
more
voltage
and
accept
more
power." "No,
use a
low resistance
load
so
it
will
draw more current and accept
more
power". "Use
a
load
which
is
somewhere
in
between."
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