ib 1.1 measurements & uncertainties

Question 1 The order of magnitude of the weight of an apple is

• A 10⁻⁴ N
• B 10⁻² N
• C 1 N
• D 10² N

Question 2 The number of heartbeats of a person at rest in one hour, to the nearest order of magnitude is

• A 10¹
• B 10²
• C 10³
• D 10⁵

Question 3 The ratio of (diameter of a nucleus)/(diameter of an atom) is approximately equal to

• A 10⁻¹⁵
• B 10⁻⁸
• C 10⁻⁵
• D 10⁻²

Question 4 The volume of the Earth is approximately 10¹² km³ and the volume of a grain of sand is approximately 1 mm³. The order of magnitude of the number of grains of sand that can fit in the volume of the Earth is

• A 10¹²
• B 10¹⁸
• C 10²⁴
• D 10³⁰

Question 5 Which one of the following contains three fundamental units?

• A Meter Kilogram Coulomb
• B Second Ampere Newton
• C Kilogram Ampere Kelvin
• D Kelvin Coulomb Second

Question 6 Which one of the following lists a fundamental unit and a derived unit?

• A ampere second
• B coulomb kilogram
• C ampere newton
• D meter kilogram

Question 7 Sub-multiples of units may be expressed using a prefix. Which one of the following lists the prefixes in decreasing order of magnitude?

• A centi- micro- milli- nano-
• B milli- centi- nano- micro-
• C centi- milli- micro- nano-
• D milli- micro- centi- nano-

Question 8 The resistive force F acting on a sphere of radius r moving at speed v through a liquid is given by F = cvr where c is a constant. Which of the following is a correct unit for c?

• A N
• B Ns⁻¹
• C Nm²s⁻¹
• D Nm⁻²s

Question 9 Which one of the following measurements is stated correctly to two significant digits?

• A 0.006 m
• B 0.06 m
• C 600 m
• D 620 m

Question 10 When a voltage V of 12.2 V applied to a DC motor, the current I in the motor is 0.20 A. Which one of the following is the output power VI of the motor given to the correct appropriate number of significant digits?

• A 2 W
• B 2.4 W
• C 2.40 W
• D 2.44 W