Chapter 1 Practice Paper: Physical Quantities, Units and Measurement — question paper

Section A: Multiple-choice questions[10 marks]

Choose the one correct answer for each question.

1. 1

   Which row shows a base quantity together with its correct SI unit?

   1. Aweight — newton (N)
   2. Bamount of substance — mole (mol)
   3. Ctemperature — degree Celsius (°C)
   4. Ddensity — kilogram per cubic metre (kg/m³)
   ( )
2. 2

   The thickness of a single sheet of paper is closest to which order of magnitude?

   1. A10⁻² m
   2. B10⁻⁶ m
   3. C10⁻¹⁰ m
   4. D10⁻⁴ m
   ( )
3. 3

   A student measures the diameter of a wire with a micrometer screw gauge. With the jaws fully closed the scale reads 0.03 mm. With the wire between the jaws the reading is 0.48 mm. What is the diameter of the wire?

   1. A0.45 mm
   2. B0.51 mm
   3. C0.48 mm
   4. D0.03 mm
   ( )
4. 4

   A student needs to measure the period of a slow pendulum as precisely as possible with a digital stopwatch. Which pair of actions achieves this?

   1. Atime one full swing, repeating five times and averaging
   2. Btime 20 complete oscillations from a fiducial marker at the centre of the swing and divide by 20
   3. Cuse the stopwatch with a display resolving 0.001 s and time a single swing
   4. Dtime from the highest point of one swing to the highest point of the next
   ( )
5. 5

   A boat is driven at 3.0 m/s across a river that flows at 4.0 m/s. The boat aims straight across the river. Which speed of the boat, in m/s, does an observer on the river bank record?

   1. A1.0
   2. B3.5
   3. C7.0
   4. D5.0
   ( )

Section B: Structured questions[20 marks]

Answer all questions in the spaces provided.

1. 1

   This question is about SI units and prefixes.

   1. (a)

      State the base quantity that is measured in amperes (A).

      [1]
   2. (b)

      A radio station broadcasts at a frequency of 98.4 MHz. Express this frequency in hertz, in standard form.

      frequency =Hz[1]
   3. (c)

      The wavelength of green light is 5.2 × 10⁻⁷ m. Express this wavelength in nanometres.

      wavelength =nm[1]
   4. (d)

      A data sheet lists the mass of a dust particle as 6.2 μg. Explain why writing this as 0.0000062 g is a less useful way to record the same measurement.

      [3]
2. 2

   A student investigates a simple pendulum. She times 20 complete oscillations three times and records 36.2 s, 35.8 s and 36.4 s.

   1. (a)

      Explain why she times 20 oscillations rather than a single oscillation.

      [2]
   2. (b)

      Calculate the average period of one oscillation.

      period =s[2]
   3. (c)

      State one reason why a digital stopwatch that reads to 0.01 s does not make the single-swing measurement accurate to 0.01 s.

      [2]
   4. (d)

      State two changes to the procedure that would improve the reliability of the period.

      [2]
3. 3

   A hiker walks 900 m due north from the campsite, then 1200 m due east to a viewpoint.

   1. (a)

      State the difference between a scalar quantity and a vector quantity, and classify distance and displacement.

      [2]
   2. (b)

      Draw a scale vector diagram and use it to find the magnitude of the hiker’s displacement from the campsite.

      displacement =m[2]
   3. (c)

      Calculate the total distance walked.

      distance =m[1]
   4. (d)

      State the direction of the displacement as an angle. You may use sin, cos or tan with the diagram in (b).

      [1]