Converting Units KHDBDCM Factor Method Because it is
Converting Units KHDBDCM & Factor Method
Because it is based on “ 10”, converting units is easy when using metric quantities. Move decimal left. Move decimal right. King Henry Died By Drinking Contaminated Milk kilo hecto deca base deci centi milli
KHDBDCM 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 letter that you start with. If you are going from milli to kilo, count K H D B D C- M 6 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 g 0. 000009 mm = ? hm. 000 000 09 750 da. L = ? m. L 300 cm = ? m 7 500 000 m. L 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 4 yr 1 4 x 365 days 1 yr x 24 hr 1 day x 60 min 1 hr = x 365 x 24 x 60 min = 2 102 400 min
5 km/h = ? m/s 5 km 1 h x 1000 m 1 km x 1 h 60 min x 1 min 60 sec 5 x 1000 x 1 m 1 x 60 sec = = 5000 m 3600 sec = 1. 4 m/s
It may help to set up the units first and then fill in the numbers: 5 Mg = ? cg 5 Mg 1 x 1 000 g Mg 1 x 100 cg 1 g = 5 x 1000 x 100 cg = 500 000 cg
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