UNIVERSITY OF JOHANNESBURG
DEPARTMENT OF PHYSICS
PRACTICAL TEST FOR PHYG1A1/L1A1 AND PHYE0A1
QUESTION PAPER X (4pgs) , DURATION OF TEST : 90 mins
STUDENT NUMBER _______________________________
Date : _______________
SURNAME AND INITIALS ________________________________________
Instructions :
Answer all questions.
Write the answers onto this question paper, and the paper should
be handed in at the end.
30 marks or more = 100 %
QUESTION-1
What is the reading on each of the precision measuring scales below ? Give a brief
indication of the procedure you followed to obtained the final value ( i.e., briefly
mention how you used the main scale and vernier scale to obtain the final reading ).
(a)
(b)
[6]
1
QUESTION-2
The length of a rectangular block of wood is 100.0 mm with an estimated error of 0.5 mm.
For the same block of wood you find the width to be 50.0 ± 0.5 mm and the thickness to be
20.0 mm ± 0.2 mm. Calculate the volume of the block in m3, find the relative error in the
volume as a percentage, and determine the absolute error in the volume in m 3 and mm3.
[6]
QUESTION-3
In each of the following examples you should rearrange the equation so that you can plot a
straight-line graph, explain (and sketch) what you would plot on the x- and y-axes, and
how you would determine the unknown quantities from the graph.
(a)
z
(b)
p
=
a b
+
t t2
z, t measured values ; a , b unknown.
= k vγ
p, v measured values ; k , γ unknown.
[6]
2
QUESTION-4
The data in the table below were obtained in the laboratory for distance moved x in
time t. The expected relationship between these quantities is
x
= v0 t + 12 at 2 ,
where initial velocity v0 and acceleration a are constants. Linearize this equation,
complete the columns in the table and then plot a graph to obtain v0 and a using the
linearized equation. Put the best and a worst straight line through the data, and
determine the slopes and intercepts. From these results estimate v0 and a and their
absolute errors.
x (m)
0.100
0.200
0.300
0.400
0.500
t (s)
3.8
6.5
8.7
10.9
12.4
[14]
3
Question 4 contin …
STUDENT NUMBER _______________________________ Date : _______________
SURNAME AND INITIALS ________________________________________
4