Sec 1 EOY Revision

Which of the following are attributes a Science student should possess?

• Curiosity

• Open-mindedness

• Perseverance

• Objectivity

Answer explanation

Creativity, objectivity, perseverance and open-mindedness are all good attributes a Science student should possess!

Reorder the options to demonstrate the sequence to a scientific investigation.

• Asking a question

• Analyze data

• Conclude

• Hypothesize

• Experiment and collect data

Answer explanation

A good scientific investigation often starts with a question that needs to be answered.

A hypothesis (guess) is made that undergoes experimentation, data collection and analysis to conclude an outcome where the hypothesis can either be proved or disproved.

A scientist wonders if the presence of water speeds up the rusting of metal and conducts a scientific investigation.

State the hypothesis of the experiment.

Answer explanation

There are a few possible hypothesis:

- Water will cause metals to rust faster.

- Water will cause metals to rust slower.

- Water does not affect the rusting of metals.

Alicia and Ben measures the length of a piece of rope, three times each.

Alicia's recorded lengths: 12.0 cm, 12.3 cm and 12.6 cm.

Ben's recorded lengths: 11.0 cm, 12.0 cm and 13.0 cm.

The actual length of the rope is 12.0 cm. Who is more accurate?

• Alicia

• Ben

Answer explanation

Accuracy refers to the closeness of agreement between a measured value and the true value of

what is being measured.

The average length of Alicia's and Ben's measurements are 12.3 cm and 12.0 cm.

Ben is closer to the actual value than Alicia. Hence Ben is more accurate in his measurement.

Alicia and Ben measures the length of a piece of rope, three times each.

Alicia's recorded lengths: 12.0 cm, 12.3 cm and 12.6 cm.

Ben's recorded lengths: 11.0 cm, 12.0 cm and 13.0 cm.

The actual length of the rope is 12.0 cm. Who is more precisse?

• Alicia

• Ben

Answer explanation

Precision refers to the closeness of agreement between measured values

obtained by repeated measurements.

The difference between the smallest and largest measurement of Alicia is 0.6 cm which is less than Ben's difference of 2 cm.

Hence Alicia is more precise.

To determine the material to be used in oven mitts, which physical property should we consider?

• electrical conductivity

• thermal conductivity

• melting/boiling point

• hardness

• strength

Answer explanation

As we do not want the oven mitts to be able to conduct heat and become hot easily, we will want a material with

LOW thermal conductivity

to protect ourselves from getting scalded!

An object has a mass of 300 g and volume of 5 cm³. Showing your workings clearly, calculate the density of the object in kg/cm³.

What is the volume of the liquid in the measuring cylinder?

• 35.0 cm³

• 36.0 cm³

• 44.0 cm³

• 45.0 cm³

Answer explanation

When reading the value of liquids with meniscus, always read the value by placing your eye right in front of the bottom of the meniscus to obtain the reading.

An object is placed in a liquid. The object sinks to the bottom. Does the liquid or the object have a higher density?

• Object

• Liquid

Answer explanation

Denser objects sink when placed in a liquid that is less dense.

Reorder the following options to demonstrate the steps to measuring the volume of an irregular object that sinks in water.

• Read the measuring cylinder to obtain the final reading

• Fill a measuring cylinder with water

• Calculate the volume by subtracting the initial reading from the final reading

• Place the object in water gently

• Read the measuring cylinder to obtain the initial reading

Answer explanation