AWM 10 Ch. 4.1A Temperature - Celsius Notes

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1 32) AWM 10 Ch. 4.1A Temperature - Celsius Notes Another quantity that we measure is temperature. Just like length, surface area and volume, we can measure temperature in different units. The US uses the Fahrenheit scale ( F) of the imperial system, while Canada uses the Celsius scale ( C) of the SI. Water freezes at 0 C or 32 F and boils at 100 C or 212 F. Since water freezes at 0 C and 3 2 F, the relationship between the two temperature systems can be calculated with the following formulas, where C represents degrees Celsius and F represents degrees Fahrenheit. Changing F to oc: C = (F 32) Ex. 1) While visiting Florida, you heard a local person say that it had been very cold overnight, as it was only 42. At first, you thought this was not cold, but then you realized the person meant degrees Fahrenheit. What was the temperature in degrees Celsius? C = (F Write down the formula C = (42 32) Put the number for F in the formula C = (10) Brackets first: Then multiplication & division C =.6 C Round to 1 decimal place and include the units! The temperature is about.6 C (which would be very cold in Florida.) Ex. 2) Mrs. Moore went to Disneyland with her family. The day they arrived it was 114 F. It was record breaking hot. What would that temperature convert to in C? C=(F 32) C=(114 32) C=4iO C=4.6 C 114 F. is equal to 46 C.

2 Temperature Ranges: Ex. ) Chinook winds are known to cause great changes in temperature over a short period of time. The most extreme temperature change in a 24-hour period occurred in Loma, Montana, on January 1, 172. The temperature rose from 4 F to 4 F. a) What were the minimum and maximum temperatures in degrees Celsius? C = (F 32) Write down the formula Starting temp: Final Temp: C=j 4 32) C (4 32) C=.( 86) C=.(17) C= 430 C= C 47.8 C C =.4 C What was the change in temperature in degrees Celsius? Temp. change final temp starting temp Temp. change =.4 C ( 47.8 C) Temp. change =.4 C C 7.2 C The temperature increased by 7.2 C. Two negatives = a positive!

3 Name: Block: Date: AWM1O Ch. 4.1B - Temperature (Fahrenheit) Notes When you have the temperature in C and want to know the temperature formula: you use this Changing OC to F: Ex. 1) You were paving a road with heated tar during a hot summer day. You noted that the external temperature of the tar was 48 C. What was this in degrees Fahrenheit? F = 2C ) Write out the equation. F =2 (48) ) Replace the C with the temperature in C. F= ) Do multiplication / division: X 48 F C 4) Do addition: + 32 Temperature Ranges: Ex. 2) Chinook winds are known to cause great changes in temperature over a short period of time. The most extreme temperature change in a 24-hour period occurred in Loma, Montana, on January 1, 172. The temperature rose from 47.8 C to.4 C. b) What were the minimum and maximum temperatures in degrees Celsius? F=2C+32 Starting temp: F =2 (-47.8) + 32 Multiplication & Division F= Addition last F=-4 Pick the right formula. What you want is in front. Final Temp: F =2 (.4) + 32 F= F = 48. a) What was the change in temperature in degrees Fahrenheit? Temp. change = final temp starting temp Temp. change = 4 F ( 4 F) Temp. change = 4 F + 4 F = 103 F The temperature increased by 103 F. Two negatives a positive!

4 Name: Block: Date: A+W Math 10 Ch Weight in the Imperial System Notes Another important measurement to be able to work with is weight. In the imperial system there are 3 major units of measurement: ton (tn), pound (ib), and ounce (oz) On the formula sheet: 1 kilogram (kg) = 2.2 pounds (Ibs) Others to know: 1 ton (tn) = 2000 pounds (ib) 1 pound (ib) = 16 ounces (oz) Ex. 1) You need 1 pound 2 ounces of Gruyère cheese, 12 ounces of cheddar cheese, and 11 ounces of Swiss cheese for a fondue recipe. How many pounds of cheese do you need in all? ipound 2 ounces = 16 ounces + 2ounces = 18 ounces Convert to oz. 18 ounces +12 ounces Add the amounts +11 ounces 41 ounces 41 ouncesx 1 pound 41= 2_=2poundsounces 16 ounces You need 2 lbs oz of cheese for the recipe. Ex. 2) The cab of your semi-trailer truck weighs 8.7 tons and the trailer weighs 6.4 tons. If the loaded gross weight of the truck is 21.3 tons, what is the weight of the load? a) in tons? Total weight = truck + trailer + load Load Total weight - truck - trailer Load2l.3 tn- 8.7tn-6.4tn Load=6.2tn The weight of the load is 6.2 tn. b) in pounds? 6.2tnx 2000lbs 1 tn bs The weight of the load is pounds.

5 Ex. 3) A 12-ounce can of vegetables costs $1.4. A 1 lb 2-oz can of the same vegetables costs $2.1. Which is the better buy? The values need to be in the same units to compare them... so convert them to $/oz. l2ozcan llb2ozcan $1.4 = $0.1242/oz 1 lb 2 oz = l6oz + 2 oz = 18 oz 12 oz $2.1 = $ /oz l8oz The 1 lb 2 oz can of vegetables is a better buy. Ex. 4) Valerie bought 4 pounds 6 ounces of steak for dinner at $2.74/lb. After removing the excess fat, she had only 4 pounds of meat. What was her true cost per pound? 4 lb 6 oz = lbs Change the ounces to a decimal in pounds 4.37 lb x $2.74 = $11. Find the total cost of the meat 1 lb $11.= $2.7/lb = $3.00/lb Divide the cost by the pounds of trimmed 4 lbs meat. The true cost for the meat was $3.00/lb. Assignment: Ch. 4.2 Practice Your New Skills

6 m Block: AWM1O Ch. 43 Imperial SI Weight Conversions Notes The SI unit for weight is the kilogram (kg) but sometimes other units can be used too. It is important to be able to convert between the different SI units, but also to be able to convert between the two systems (SI and Imperial). On the formula sheet: 1 kilogram (kg) = 2.2 pounds (Ibs) Others to know: 1000 grams (g) = 1 kilogram (kg) 1000 milligrams (mg) = 1 gram 1 tonne (t) = 1000 kilograms Ex. 1) A recipe for cornbread calls for 120 g of flour, 170 g of cornmeal, and 0 g of sugar. If you double the recipe, what is the total weight of the dry ingredients in kilograms? 120 g g + 0 g = 340 g Add the weights together 340 g x 2 = 680 g Multiply by 2 to double the recipe 680 g x 1 kg = 0.68 kg Convert grams to kilograms l000g The total weight of the dry ingredients is 0.68 kg Ex. 2) You are baking apple pies. According to the recipe, you need 6 pounds of apples. The bag of apples you bought only shows the weight in kilograms. How many kilograms of apples do you need? 6lbx 1kg =2.73 kg 2.2 lb You need 2.73 kg of apples for the pies. Ex. 3) The cost of bananas is $0.4/lb at one store, but you see an advertisement for bananas on sale at another store for $1.0/kg. Which is the better buy? $0.4 x 2.2 lb = $1.08/kg llb 1kg The sale at the second store is a better buy (by $0.03/kg)

7 Name: AWM1O Block: Ch. 4.4 More Conversions Notes Sometimes we need to convert a unit of volume into a unit of weight (or the way around). In cases like this, we need to make a conversion factor specific to example (numbers to do this will be given in the questions). Some more conversions 1 1 g 1 that might help with your homework: lbo.4kg oz28.3 tno.t Ex. 1) How many bushels of flax seed are there in 2.4 tonnes, if the conversion factor is bushels/tonne? 2.4 There t x bushels = 4. bushels are it 4. bushels in 2.4 tonnes. the other Ex. 2) You are making chicken kebabs for 14 people. The recipe suggests about 7 oz of chicken per person. At the grocery store, the weight of chicken is labelled in kilograms. How much chicken do you need to buy? 14 people x 7 oz x 28.3 g x 1 kg = 2.77 kg 1 1 oz person i000g You need to buy 2.77 kg of chicken to feed your guests.