HP HP-15C - Page 40

40 Section 3: The Memory Stack, LAST X, and Data Storage
Example: Two close stellar neighbors of Earth
are Rigel Centaurus (4.3 light-years away) and
Sirius (8.7 light-years away). Use the speed of
light, c (3.0×10
8
meters/second, or 9.5×10
15
meters/year), to figure the distances to these
stars in meters. (The stack diagrams show only
one decimal place.)
T
t
z
y
y
Z
z
y
x
x
Y
y
x
4.3
4.3
X
x
4.3
4.3
9.5 15
Keys:
4.3
v
9.5 ‛ 15
LAST X:
/
/
/
/
T
y
y
y
x
Z
x
y
x
4.1 16
Y
4.3
x
4.1 16
8.7
X
9.5 15
4.1 16
8.7
9.5 15
Keys:
*
8.7
|K
LAST X:
/
9.5 15
9.5 15
9.5 15
T
x
x
Z
4.1 16
x
Y
8.7
4.1 16
(Rigel Centaurus is
4.1×10
16
meters away.)
(Sirius is 8.3×10
16
meters away.)
X
9.5 15
8.3 16
Keys:
*
LAST X:
9.5 15
9.5 15