Physics Quiz on Quantities and Units

What are the SI base units of k?

• kg-1 m-1 s2 K

• kg-1 m-2 s2 K

• kg m s-2 K-1

• kg m2 s-2 K-1

Which diagram best represents the calibration graph needed to obtain an accurate current reading?

Which definition is correct and uses only quantities rather than units?

• Density is mass per cubic metre.

• Potential difference is energy per unit current.

• Pressure is force per unit area.

• Speed is distance travelled per second.

If systematic errors cause t and h to be measured incorrectly, which error must cause g to appear greater than 9.81 ms-2?

• h measured as being smaller than it actually is and t is measured correctly

• h measured as being smaller than it actually is and t measured as being larger than it actually is

• h measured as being larger than it actually is and t measured as being larger than it actually is

• h is measured correctly and t measured as being smaller than it actually is

A single sheet of aluminium foil is folded twice to produce a stack of four sheets.

The total thickness of the stack of sheets is measured to be (0.80 ± 0.02) mm.

This measurement is made using a digital caliper with a zero error of (−0.20 ± 0.02)mm.

What is the percentage uncertainty in the calculated thickness of a single sheet?

• 1.0%

• 2.0%

• 4.0%

• 6.7%

A stone sinks in water. What is a possible value for the density of the stone?

• 8 × 102 kg m-3

• 2 × 103 kg m-3

• 8 × 103 N m-3

• 2 × 104 N m-3

Gm, Tm, μm and pm are all units of length. Which unit is the largest and which unit is the smallest?

Two measurements for a solid sphere are shown.

mass = (32.5 ± 0.1) g

diameter = (1.87 ± 0.04) cm

These values are used to determine the density of the sphere.
What is the percentage uncertainty in the density?

• 2.4%

• 4.6%

• 6.1%

• 6.7%

What is the displacement of the ball from X to Y?

• 2.0 m

• 2.0 m due south

• 3.1 m

• 3.1 m due south

What represents a physical quantity?

• 3.0

• kilogram

• 7.0N

• 40%