T.H. The Professional Development Service for Teachers is funded by the Department of Education and Skills under the National Development Plan The Height Of A Tree
PDST Resources for Leaving Certificate Physics 2 The height of a tree How would you measure the height of this tree?
PDST Resources for Leaving Certificate Physics 3 We measured a student’s height. His height was 1.7 m. Remember to hold the metre sticks vertically. Avoid the error of parallax when taking the reading.
PDST Resources for Leaving Certificate Physics 4... and the length of his shadow His shadow turned out to be 3.2 m long. How are these measurements going to help us to find the height of the tree? What did we do next?
PDST Resources for Leaving Certificate Physics 5 The length of the tree’s shadow This was 16.3 m in length. The student’s height was 1.7 m. His shadow had a length of 3.2 m. How does this relate to the height of the tree?
PDST Resources for Leaving Certificate Physics 6 Look at these similar triangles.
PDST Resources for Leaving Certificate Physics 7 Can you work out the tree’s height now?
PDST Resources for Leaving Certificate Physics 8 Answer
PDST Resources for Leaving Certificate Physics 9 What Next? Use this method to find the height of a tree or building near you. Remember: