Presentation on theme: "ACTIVITY 2 - HOW TALL IS… ? Tuesday November 30th, 2010 Rollie Comeau Watson Lake Secondary School."— Presentation transcript:
ACTIVITY 2 - HOW TALL IS… ? Tuesday November 30th, 2010 Rollie Comeau Watson Lake Secondary School
ACTIVITY 2 How tall is …? Specific Outcomes A and 3.2 B and 2.7 B , 3.6 and 3.7 B and 4.2 B , 5.4, 5.7, and 5.8
ACTIVITY 2 How tall is …? Material needed: ProtractorTube (one foot long) TapeString WeightPencil PaperCalculator Warm Clothing
ACTIVITY 2 How tall is …? Problem You need to cross a particularly swift creek. It is too wide to jump. A tree stands close to the edge of the creek. How can you determine if the tree is long enough to safely span the creek?
ACTIVITY 2 How tall is …? Tree Ground Distance
ACTIVITY 2 How tall is …? To solve this problem, the concepts of similar triangles, right-triangles, trigonometry, parallel lines and transversal lines, and/or referents can be introduced in your lesson.
ACTIVITY 2 How tall is …? Lets use trigonometry to solve this problem. The three basic trigonometric ratios involve two sides of a right-triangle and one of the two acute angles.
ACTIVITY 2 How tall is …? In our case, we are looking for the height of the tree - this is the unknown value we are seeking.
ACTIVITY 2 How tall is …? The distance from the tree can be assessed with the help of a long measuring tape. This is one of our known values. We are missing an acute angle…
ACTIVITY 2 How tall is …? From the ground, looking up at the top of the tree, we could possibly determine the angle of elevation. For this, you will need to consult a surveyor who can measure it for you or, construct a simple device that can do it for you!
ACTIVITY 2 How tall is …? A simple clinometer comes to mind… lets construct one!
ACTIVITY 2 How tall is …? Before going outdoors, you will need to determine the height of your eyesight. For convenience, a measuring tape has been placed on the wall to assist you. Record this value on the Activity 2 data sheet provided.
ACTIVITY 2 How tall is …? As a group, select a set distance from the object to be measured. Record this value as Ground Distance.
ACTIVITY 2 How tall is …? Each member of the team should: a)Use the clinometer (viewing through the tube at the top of the tree) b)Take the reading off the clinometer (angle in degrees) c)Record the measurement read by b)
ACTIVITY 2 How tall is …? Upon return, a)Draw a diagram representing the problem we are attempting to solve b)Place all measurements in the diagram c)Use trigonometry to solve the problem
ACTIVITY 2 How tall is …? Share your answer with your group. 1.Discuss why your answer may vary compared to others. 2.Discuss factors that may influence your answers.