Alternative A
Question 1A
The diagram above illustrates a metre rule whose centre of gravity G is suspended from a rigid pointer P. The distance X between G and P is measured and recorded.
The metre rule is slightly displaced sideways and released so that it performs simple oscillations.
The time, t for 20 complete oscillations and the period T of the oscillations are determined and recorded.
The procedure is repeated for four other values of x.
Fig. 1(a) and Fig. 1(b) on page 3, illustrate the distances xi and the corresponding times ti respectively, where i = 1,2,3,4 and 5.
(i) Measure and record xi.
(ii) Read and record ti.
(iii) In each case, evaluate x2, T and T2x.
(iv) Plot a graph of x2 n the vertical axis and T2x on the horizontal axis, starting both axes from the origin (0, 0).
(v) Determine the slope, s, of the graph.
(vii) State two precautions you would take if you were to perform this experiment in the laboratory
Observation
The expected response:
- Five values of x correctly measured and recorded to at least 1 d.p. and
- within tolerance of ± 0.1 cm
- (Deduct 1 mark for each wrong or missing value)
- Five values of tcorrectlyread and recorded to at least 1 d.p in seconds
- (Deduct 1 mark for each wrong or missing value)
- Five values of x2correctly evaluated to at least 2 d.p.
- (Deduct ½ mark for each wrong or missing value)
- Five values of Tcorrectly evaluated to at least 2 d.p.
- (Deduct ½ mark for each wrong or missing value)
- Five values of T2x correctly evaluated to at least 2 d.p
- (Deduct ½ mark for each wrong or missing value)
- Composite table showing at least x,t,x2,Tand T2x.
- Plot a graph of reasonable scales
- Draw line of best fit
- Determine the slope
- Evaluate k =
- State any two of the following precautions
e.g
- Avoided/avoid parallax error in reading metre rule/stop clock/stop watch
- Repeated readings stated
- Noted/corrected zero error on metre rule/stop clock/stop watch
- Ensured/ensure pin is firmly clamped
- Avoided/avoid draught