1 / 17

Unit 21 Formula

Unit 21 Formula. Unit 21 Formula. 21.1 Using Formula. 4cm. w. 8 cm. l. Question What are the perimeter length and area if and ?. The perimeter length, P , and area, A , of a rectangle are given by the formulae where l is the length and w the width of the rectangle.

aalston
Download Presentation

Unit 21 Formula

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Unit 21Formula

  2. Unit 21Formula 21.1 Using Formula

  3. 4cm w 8 cm l Question What are the perimeter length and area if and ? The perimeter length, P, and area, A, of a rectangle are given by the formulae where l is the length and w the width of the rectangle. Solution (a) Solution (b) ? ? ? ? ? ? ? ?

  4. Unit 21Formula 21.2 Constructing Formula

  5. When repairing air conditioning systems, an emergency engineer charges a basic fee of J$3000 plus J$1200 per hour. Question What does the engineer charge in total if the repair takes 6 hours? Question Find a formula for calculating the engineer's charge for repair work which takes n hours. Solution C = J$3000 + J$1200 × 6 C = J$3000 + J$7200 C = J$10200 Solution Let C = Charge So C = fixed charge + hourly charge × no. of hours C = J$3000 + J$1200 × n C = J$3000 + J$1200n ? ? ? ? ? ? ? ? ?

  6. Unit 21Formula 21.3 Negative Numbers

  7. Rules to remember Calculate 4 + (−10) = −6 −6 + 8 = 2 −4 − 5 = −9 −6 + (−7) = −13 (−40) ÷ (5) = −8 (−24) ÷ (3) = −8 (−40) ÷ (−5) = 8 (−6) × 7 = −42 ? ? ? ? ? ? ? ?

  8. Unit 21Formula 21.4 Temperature Differences

  9. What is the difference in temperature between Use information given on the above to answer these questions. Kingston and Singapore 4 Kingston and London 25 Kingston and Vancouver 29 London and New York 3 London and Sydney 26 Lima and Kingston 0 Oslo and Kingston 30 Moscow and Kingston 34 ? ? ? ? ? ? ? ?

  10. Unit 21Formula 21.5 Substitution in Formula

  11. l = (40 + 0.02T) cm Question What is the length of the rod when (a) T = 50˚C (b) T = −10˚C The length of a metal rod changes with temperature according to formula above; where T is the temperature in ˚C (a)l = (40 + 0.02 x 50) cm = (40 + 1) cm = 41cm Solution (b) l = (40 + 0.02 x −10) cm = (40 + −0.2) cm = 39.8cm ? ? ? ? ? ?

  12. Unit 21Formula 21.6 More Complex Formula

  13. The formula gives the focal length f for a lens Question What is the value of f, if u= 10cm and v = 8cm Solution ? ? ? ? ? ? Hence

  14. Unit 21Formula 21.7 Changing the Subject

  15. The formula that connects ˚Celsius (C) and ˚Fahrenheit (F) is Question Rewrite the formula in the form C = ...... Solution Take 32 from both sides of the formula So ? Multiply by 5 throughout ? Divide by 9 throughout ?

  16. Unit 21Formula 21.8 Pendulums

  17. The period of revolution, T, of a pendulum of length l is given by the formula when G is a constant. Solution Divide both sides by to give Problem Make l the subject of this equation. ? Square both sides ? ? Multiply both sides by G to give ?

More Related