Thurs 20th Sep - Inverse Proportion

LEARNING OBJECTIVE: How to solve problems that use the expression inverse proportion / inversly proportional.
SUCCESS CRITERIA: You will be able to find the constant of proportionality and equaiton of inverse proprotion problems and then use this equation to solve problems.

ENGAGEMENT ACTIVITY:
1. The illumination, L, provided by a torch is inversely proportional to the square of the distance, d, from the torch.
When L = 2, d = 10.
a) Find an equation expressing L in terms of d (1)
b) Find the value of L when d=2
c) Find the value of d when L = 8

2. In an experiment measurements of t and h  were taken.
These are the results:

t    2           5          6
h   10       62.5       90

Which of thee rules fits the results

a) h is proportional to  t   
b) h is proportional to  t²     
c) h is proportional to  t3  
    
LESSON: Work Through this Lesson, using the example questions with students both as a group and as individuals. When they are comfortable with the concepts and processes then they can have a go at Ex 9C on page 224/225 of HIgher Text Book.

EXTENSION: A* Exam Questions (11,12 & 13 on page 226

HOMEWORK: There are two Mymaths tasks on Proportion to be attempted before NEXT THURSDAY 28th Sep