Revision SI

What is the physical quantity?

• the quantity that can be measured by scientific instruments

• the quantity that has magnitude and direction

• the quantity that cannot be measured

• the quantity that has magnitude but no direction

S.I. unit for length

• kilogram, kg

• meter, m

• kelvin, K

S.I. unit for mass

• second, s

• ampere, A

• kilogram, kg

S.I. unit for time

• kelvin, K

• second, s

• ampere, A

why we need to write in standard form?

• because the number is too big

• because the number is too small

• easy to read

write the following number in standard form

0.00000005

90000000000000 in standard form is

756000 g = ________ kg

• 7.56 kg

• 7560 kg

• 756 kg

0.00005 m = ________ mm

• 0.05 mm

• 0.5 mm

• 5 mm

8916.45 kA = _______ A

• 8.91645 A

• 89.1645 A

• 8916450 A