Welcome to
Double Churches’
MATH TRAIL
Math
Trail Station # 7
Check that you have
everything you need for this station:
pencil - paper - ruler -
calculator - protractor - compass
MATH TRAIL
# 7
At this station you will
be working with angles and measurements of angles. An angle is two rays that meet at one
endpoint. There are many types of
angles. The most common type of angle
is a right angle, where two rays ( or lines) meet perpendicularly, that is to
form a 90°
angle. Think of a door meeting the frame or the corner of a sheet of paper. These are examples of right angles. Other types of angles include acute angles that measure less than 90°; obtuse angles that measure greater than 90°,
or an angle that is 180° or a straight
line.
YOUR TASK:
Your task is to use the
clock hands on the clock near the library to find the degree measure of the angles
made by the hands of a clock at certain times of the day. First, use your compass to make a circle to
represent a clock. Put the point of the
compass in the center of your paper
and, making sure to keep the point in place, draw a circle with the pencil end
of the compass. Now take the protractor
and put the tiny circle in the middle of the ruler edge on top of the point
made by the compass and make a pencil mark through the hole. Take a minute to look at the
protractor. Do you see the numbers that
are going around the semi-circle part of the tool? These are the degree marks.
Do you notice that there is a 0 and a 180 at each end and two 90s in the
middle? Since we can measure an angle
from either side of a line we must have
markings from both sides to help find the correct degree measure. Starting from the right side of the
protractor, still placed with the center of the circle on the tiny hole of the
protractor, make an angle that is 90°.
Make sure to mark the start point at zero and the end point on your circle at
90°. Draw lines from the center point to the edge
of your circle clock where you made the
two marks. Does this look like it could
be 3 o’clock? If so, then repeat the process starting at 3
o’clock to mark 6, 9 and 12 o’clock.
Now that you have drawn your clock you will find out the measure of
angles for different times of the day.
Remember to always have the 0 from either the left side or right side on
one line segment (like the hour hand) and measure to the other line segment
(the minute hand). Tick, Tock, Time to Rock.....Measure and record the
degree angle when the clock shows 2:00.
Measure the degree angle when the clock shows 5:00. Measure the degree angle when the clock
shows 10:00. To measure this move the
protractor to the line made when you measured 180°
at 6:00. Measure from 6:00 to 10:00 and
add the numbers.
If you have time, take the measurement of the degree angle at
2:00 and add to it the degree angle 3 hours later. (Hint: start at 2:00 and measure the hour hand
only!!!) To that add the degree angle 5
hours after that. Finally, at the degree angle 2 hours later. You should have made a complete circle of
the hour hand of the clock. What does the sum of the angles
measure? This is also the measurement
of the total degrees in any circle shape, including a clock, a jar lid, a compact
disc or any flat round object.