Light Bulb Binary (Page 2 of 3) in pdf

Light Bulb Binary Page 2

the fours place. Multiply 4 by 2 and get the eights place. Multiply 8 by

2 and get the sixteens place, and so on:

Binary Place Value

Create Binary Numbers

Have students place the five light bulb cards on the five columns of the

place value chart on the worksheet with the “off” side showing.

Say, “Suppose we wanted to represent the numeral 2 with light bulbs.

Looking at the place values, what light bulbs would we have to turn

on?”

Wait while students figure this out by turning over the light bulb(s)

needed.

Answer: You only need the light bulb in the twos place to be “on” (2 =

0 = 2).

In binary, a two is shown with the light bulb in the twos place “on” and

the ones place “off.” And “on, off” signals “10.” It looks like a ten, but

say “one zero.”

“Use the light bulbs to show a five.”

Answer: Turn on the light bulbs in the fours and the ones places to

make a five (4 + 0 + 1 = 5).

For 5, the light bulbs read “on, off, on” or 101 (“one zero one”).

“How about an 11?”

Answer: The light bulbs read “on, off, on, on” (8 + 0 + 2 + 1 = 11). It

looks like 1011, “one zero one one.”

Ask students to show you 28, 15, 36, 7.

Students can now work together to quiz each other.

Have one student put a binary number on the board, such as 10101,

and others figure out its decimal equivalent with the light bulb cards.

Ask, “What happens when we want to show a 38 or a 61 or 103?”

Students will follow the pattern on the place values chart to add

columns (32, 64, 128, and so on).

Light Bulb Binary Page 2