By The End Of The Subtopic Learners Should Be Able To; 


Physical quantity  Name of S.I. unit  Symbol for unit 

Length  Metre  M 
Mass  Kilogram  Kg 
Time  Second  S 
1000W = 1kW
k is the prefix (kilo); k = 1000
0.001g = 1mg
m is the prefix (milli); m = $\frac{1}{1000}$ = 0.001
Name  symbol  Factor  Scientific notation 

tera  T  1 000 000 000 000  10^{12} 
giga  G  1 000 000 000  ${10}^{9}$ 
mega  M  1 000 000  ${10}^{6}$ 
kilo  K  1 000  ${10}^{3}$ 
hecto  H  100  ${10}^{2}$ 
deca  Da  10  ${10}^{1}$ 
deci  d  0,1  ${10}^{1}$ 
centi  c  0,01  ${10}^{2}$ 
milli  m  0,001  ${10}^{3}$ 
micro  µ  0,000 001  ${10}^{6}$ 
nano  n  0,000 000 001  ${10}^{9}$ 
pico  p  0,000 000 000 001  ${10}^{12}$ 
$3450000000=3.4\times {10}^{9}m$
a. Read the fixed scale first from the zero mark of the Vernier scale.
b. Look at where the divisions on the Vernier scale coincide with that on the main scale.
Reading: 4 on the main scale coincides with the 6 on the sliding scale
c) Add the reading from the main scale to that of the Vernier scale (remember the Vernier scale is a 1/100 cm)
From Fig 1.3 and Fig 1.4:
Reading = 1.30 cm + 6/100 cm
= 1.36 cm
To find the area (A) of this rectangle you multiple its length (L) with its width (W).
A = L x W
= 5 m x 3 m
= 15 ${\mathrm{m}}^{2}$
The units are also multiplied together to give ${\mathrm{m}}^{2}$
volume = L x w x h
(length, width and height are all in centimetres, therefore you multiply the units together)
= cm x cm x cm
= ${\mathrm{cm}}^{3}$
For example, for a square measuring 2 m each side;
perimeter for the square = 2 m + 2 m + 2 m + 2 m
= 8 m [not 8 ${\mathrm{m}}^{4}$]
George has a continuously leaking tap in his kitchen. He is trying to figure out the time it takes for one drop of water to move from the tap and hit the base of the kitchen sink.
Here are the challenges he faces
1. The drop is moving too fast between the tap and base of the sink. (Distance too short)
2. As soon as he starts the stop watch (that is when the drop leaves the tap), he has to stop it (that is when the drop makes the sound as it hits the base of the sink). This gives him a ridiculous time interval due to how fast he reacts between starting the stop watch and stopping it (his reflex action).
How would you help George get an accurate time interval for the drops?
Oscillation is a complete cycle/swing (to and fro motion) from the diagram below, Fig.1.1.9. One complete oscillation is done when the bob swings from A to B, then to C through A and finally back to A.
A physics student is investigating the oscillation of a pendulum.
The apparatus is set up as shown in Fig. 1.1.10
She proceeds as following:
(i) The diagrams are drawn to 1/5 scale.
Calculate, and record in Table 1.1.4, the actual heights H of the pendulum bob above the bench. [2]
Table 1.1.4  

(c) (i) For each value of height h, calculate the time T for one complete oscillation, using the equation T = $\frac{\mathrm{t}}{10}$.
Record these values in Table 1.1.4.
(ii) Calculate the values of ${\mathrm{T}}^{2}$ and record these in the table. [1]
(d) Plot a graph of ${\mathrm{T}}^{2}$ / ${\mathrm{s}}^{2}$ (yaxis) against H / cm (xaxis).
(e) Determine the gradient G of the graph.
Show clearly on the graph how you obtained the necessary information. [1]
G = (1.96  0.80)${\mathrm{s}}^{2}$ ÷ (10  40)cm
=  0.04 ${\mathrm{s}}^{2}$/cm
The following calipers have zero errors as indicated in each case. Find the actual reading for each caliper.
Zero error = +0.02 cm Zero error = 0.04cm
The following methods can be used to find the volume of irregular shaped bodies.
1) Using the displacement can:
2) Placing the object in a measuring cylinder:
Density = $\frac{\mathrm{mass}}{\mathrm{volume}}$
$\rho $ = $\frac{\mathrm{m}}{\mathrm{v}}$