Unit 1: Making Measurements and Time - PHYSICS S3B

Unit 1 of Physics IGCSE S3B

Kilograms (kg).

What is the SI unit for mass?

One period is the time it takes for a pendulum to make one oscillation — which is a full swing from left to right and back again.

What is one period?

Metres (m).

What is the SI unit for length?

Density tells us how concentrated its mass is of a substance.

What is density?

Measuring with a Vernier Caliper:

Measured length at Main Scale (usually in cm/inches) + measured length in Vernier Scale (usually in mm)

→ Line up the object between the jaws of the vernier caliper (either measuring external or internal dimension) and get the measurement of the object before the zero mark on the vernier scale. Starting from the zero going to the right, on the vernier scale, find a line that aligns PERFECTLY with the corresponding line on the main scale. That line would be 0.1x of the main scale. Add the two measurements together to find the TOTAL measurement.

Eg. Main scale: 1.1cm Vernier scale: 0.2 cm. Total: 1.3 cm.

How do you measure lengths with a vernier caliper?

Measuring with a Micrometer:

Measured length at main scale (usually in mm) + measured length at circular scale (usually in 0.01mm)

→ Line up the object between the anvil and the spindle and get the measurement of the object at the main scale. Find the line that aligns perfectly with the horizontal number line of the main scale at the circular scale. This is your circular scale measurement (usually in 0.01x of the main scale, so 0.01mm). Add the two measurements together to get the total measurement!

Eg. Main scale = 12.5mm. Circular scale = 0.03mm. Total: 12.53mm.

How do you measure lengths with a micrometer/screw gauge?