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Converting Units. KHDBDCM & Factor Method. Because it is based on “10”, converting units is easy when using metric quantities. K ing kilo H enry hecto D ied deca B y base D rinking deci C ontaminated centi M ilk milli. Move decimal left. Move decimal right.
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Converting Units KHDBDCM & Factor Method
Because it is based on “10”, converting units is easy when using metric quantities. King kilo Henry hecto Died deca By base Drinking deci Contaminated centi Milk milli Move decimal left. Move decimal right.
K H D B D C M Converting left to right – move decimal right. 4 km to ? cm K-H D B D C 1 2 3 4 5 SO move decimal 5 places right 4 km to 400000 cm
Remember not to count the letterthat you start with.If you are going from milli to kilo, countK H D B D C- M • 5 4 3 2 1 and move the decimal 6 places to the left.
Try these using K H D B D C M: 3000 kg = ? g 3 000 000 g 0.000009 mm = ? hm .000 000 000 09 750 daL = ? mL 7 500 000mL 300 cm = ? m 3 m
Factor Conversion Other names: Unit Cancellation/ Dimensional Analysis While the King Henry method is easy, it only works when converting between kilo and milli because these prefixes differ consecutively by 101. For example, how would you change from Mg to cg or km/hr to m/s ? Mega and hours aren’t in the King Henry tragedy!
In factor conversion, the idea is to multiply by a factor equivalent to one, that cancels out units, until the desired result is achieved. 4 yr = ? min x x 4 yr 1 365 days 1 yr 24 hr 1 day x 60 min 1 hr = 4 x 365 x 24 x 60min = 2 102 400 min
5 km/h = ? m/s x x 5 km 1h 1000 m 1 km 1 h 60 min x 1 min 60 sec = 5000 m 3600 sec 5 x 1000 x 1 x 1 m 1 x 1 x 60 x 60 sec = = 1.4 m/s
It may help to set up the units first and then fill in the numbers: 5 Mg = ? cg 1 000 000 100 x x 5 Mg 1 g Mg cg g 1 1 = 5 x 1000 000 x 100 cg = 500 000 000 cg