Question 1 Report
TEST OF PRACTICAL KNOWLEDGE QUESTION
You are provided with a metre rule, lens, screen, ray box, and other necessary apparatus.
i. Set up the experiment as shown in the diagram above. Measure and record the diameter a\(_{0}\), of the illuminated object.
ii. Place the object at a distance x= 25cm from the lens. Adjust the screen until a sharp image is obtained on the screen.
iii. Measure and record the diameter, a, of the image.
iv. Measure and record the distance v between the lens and the screen.
v. Evaluate y = P = \(\frac{1+y^{2}}{y}\) and T= x+v.
vi. Repeat the procedure for x = 30cm, 35cm, 40cm and 45cm. In each case, determine the corresponding values of a,v,y, P and T.
vii. Tabulate your results.
viii. Plot a graph of P on the vertical axis against T on the horizontal axis starting both axes from the origin (0,0).
ix. Determine the slope, s, of the graph.
x. Determine the intercept, c, on the horizontal axis.
xi Evaluate K = \(\frac{c}{2}\)
xii. State two precautions taken to ensure accurate results.
(b)i. Explain the statement, the focal length of a converging lens is 20cm.
ii. An object is placed at a distance x from a converging lens of focal length 20cm. If the magnification of the real image is 5, calculate the value of x.