Physical Quantities & Measurement Techniques (Cambridge (CIE) IGCSE Physics)

A student has a pile of A4 paper for his computer printer.

Fig. 1.1 shows the dimensions of the pile of paper.

The pile contains 500 sheets of paper.

Calculate the average thickness of one sheet of paper.

average thickness = .................................................... cm 

Show that the pile of paper has a volume of 3000 cm³. Use the information shown in Fig.1.1.

The student measures the total mass of the paper in the pile.

State the name of a device used to measure mass.

The mass of the paper in the pile is 2400 g.

Calculate the density of the paper.

density = .............................................. g/cm³

A teacher investigates the reaction time of five students. A 0.50 m ruler is held above the hand of a student before being allowed to fall. The arrangement is shown in Fig. 3.1.

As soon as the ruler falls the student closes their hand, catching the ruler. The further the ruler falls, the greater the reaction time of the student. The results obtained are shown in Fig. 3.2.

Using the results shown in Fig. 3.2, calculate the average distance that the ruler drops.

average distance = ................................................... cm 

List the students in order of their reaction times, with the shortest reaction time at the top of the table. One has been done for you.

In a similar investigation, a ruler drops a distance of 11.0 cm and has an average speed of 16 cm / s. 

Calculate the reaction time.

   reaction time = ...................................................... s 

Fig. 1.1 shows a large tank containing water. The tank leaks. Drops of water fall from the tank.

The drops hit the ground at a regular rate.

A student measures the time interval between two drops of water hitting the ground.

 They use a stopwatch and repeat the procedure three times. Fig. 1.2 shows each stopwatch reading.

(i) On the line below each stopwatch, state the time readings shown, in seconds.

[1]

(ii) Calculate the average time interval between two drops of water hitting the ground.

average time = ....................................................... s [2]

Another student measures the average time taken for a drop of water to fall from the tank to the ground. The time taken is 1.6 s.

Calculate the average speed of this drop of water.

average speed = ................................................... m/s 

A student has a piece of metal that has an irregular shape. The weight of the metal is 3.0 N.

Calculate the mass of the metal.

mass = ..................................................... kg 

Fig. 2.1 shows the piece of metal, a measuring cylinder and a beaker containing water.

(i) Describe how to determine the volume of the metal, using the equipment in Fig. 2.1.

[4]

(ii) Explain why the procedure in (b)(i) is not suitable for finding the volume of a piece of low-density wood that is of similar shape and size to the piece of metal in (a).

[1]

(iii) The mass of another piece of metal is 405 g and its volume is 150 cm³.

Calculate the density of the metal. State the unit.

density = .......................................................... [3]

Extended tier only

Two students are discussing mass and weight.

Student 1 claims that a person's weight will be different on Mars than it is on Earth. 

Describe the difference between mass and weight, and explain whether you agree with Student 1.

Extended tier only

Identify the vector quantities.

Tick all the boxes that apply.

  displacement

distance

speed

velocity

Extended tier only

Two forces act at right angles to one another: a 35 N force acts to the right and a 42 N force acts downward.

Construct a scale diagram showing the effect of these two forces, and label the resultant force as X.

Use the scale 10 N = 1 cm

Extended tier only

Calculate the magnitude and direction of the resultant force of the forces acting from part (c)

magnitude of resultant force = ....................................

direction of resultant force = .................................... to the horizontal

A student uses a stopwatch in a timing experiment.

Fig. 1.1 shows the stopwatch readings.

Calculate the time interval between the two readings.

time interval = ...................................................... s 

A device has a light-emitting diode (LED) that flashes briefly at regular intervals.

Describe how to determine accurately the average time for each interval, using a stopwatch.

A student places 8 similar coins in a pile, as shown in Fig. 1.1.

The height of the pile of coins is 2.4 cm.

Calculate the average thickness of one coin.

average thickness = .................................................. cm 

Fig. 1.2 shows the pile of coins, a measuring cylinder and a beaker containing some water.

Describe how the student can measure the volume of one of the coins using the set-up shown in Fig. 1.2.

Extended tier only

An object of weight W is suspended by two ropes from a beam, as shown in Fig. 1.1.

Fig. 1.1

The tensions in the ropes are 45.6 N and 81.1 N, as shown.

Using a scale of 1 cm = 10 N, construct a scale drawing to show the resultant force of the two tensions.

Clearly label the resultant force.

Extended tier only

Using your scale diagram from part (a), determine the magnitude and direction of the resultant force.

magnitude of resultant force = ....................................

direction of resultant force = .................................... 

Extended tier only

State the value of W.

W = .................................... 

Extended tier only

State another vector quantity other than a type of force.

Extended tier only

State the definition of a vector quantity.

Extended tier only

A list of vector quantities and their SI units are given in the following table.

Complete the information missing from the table.

Extended tier only

A horizontal force of 136 N to the right, and a vertical downward force of 54 N act on an object perpendicularly to one another.

By use of a scale diagram (not by calculation) determine the magnitude of the resultant force.

magnitude of resultant force = .................................... 

Extended tier only

Using the information from part (c), determine the direction of the resultant force. 

direction of resultant force = .................................... from the horizontal

Extended tier only

A bucket of water hangs from a rope attached to a pole as shown in Fig. 1.1.

Fig. 1.1

The tension force,  = 31 N and the ropes are perpendicular to one another.

Calculate the magnitude of the downward force acting on the bucket of water.

 magnitude of downward force = .................................... 

State the name of the downward force acting on the bucket.

Extended tier only

Weight is a vector quantity. Name one other vector quantity.

The bucket has a mass of 0.65 kg.

Calculate the mass of the water in the bucket.