Unit 1 - Measurement

A student models the relationship between the pressure p of a gas and its temperature T as p = x + yT.

The units of p are pascal and the units of T are kelvin. What are the fundamental SI units of x and y?

• A

• B

• C

• D

What is the unit of electrical potential difference expressed in fundamental SI units?

• kg m s^-1 C^-1

• kg m² s^-2 C^-1

• kg m² s^-3 A^-1

• kg m² s^-1 A

What is the best estimate for the diameter of a helium nucleus?

• 10^–21 m

• 10^–18 m

• 10^–15 m

• 10^–10 m

Which is a unit of force?

• J m

• J m^–1

• J m s^–1

• J m^–1 s

How many significant figures are there in the number 0.0450?

• 2

• 3

• 4

• 5

What is a correct value for the charge on an electron?

• 1.60 x 10^–12 μC

• 1.60 x 10^–15 mC

• 1.60 x 10^–22 kC

• 1.60 x 10^–24 MC

A swimming pool contains 18×10⁶ kg of pure water. The molar mass of water is 18gmol^–1. What is the correct estimate of the number of water molecules in the swimming pool?

• 10⁴

• 10²⁴

• 10²⁵

• 10³³

Which of the following is a derived unit?

• Mole

• Kelvin

• Coulomb

• Ampere

Which of the following expresses the watt in terms of fundamental units?

• kg m² s

• kg m² s^-1

• kg m² s^-2

• kg m² s^-3

Which of the following is a fundamental unit?

• Ampere

• Coulomb

• Ohm

• Volt