1a. (i) Using the spring balance provided, determine the weight of an object of mass M = 5.0 g. Record this weight as W\(_1\).
(ii) Determine the weight of the object when completely immersed in water contained in a beaker as shown in the diagram. Record the weight as W\(_2\).
(iii) Determine the weight of the object when it is completely immersed in the liquid labelled "L". Record the weight as W\(_3\). Evaluate u = (W\(_1\) - W\(_2\)) and v = (W\(_1\) - W\(_3\)).
(iv) Repeat the procedure with the objects of masses M = 10, 15, 20, and 25 g. In each case, evaluate v = (W\(_1\) - W\(_3\)) on the vertical axis against u = (W\(_1\) - W\(_2\)) on the horizontal axis.
(v) Determine the slope, s, of the graph.
(vi) State two precautions taken to ensure accurate results.[21 marks]
bi. A piece of brass of mass 20.0 g is hung on a spring balance from a rigid support and completely immersed in kerosene of density 8.0 × 10\(^2\) kgm\(^{-3}\). Determine the reading on the spring balance. [g = 10 ms\(^{-2}\), density of brass = 8.0 × 10\(^3\) kgm\(^{-3}\)]
(Provide your answer with unit e.g 123.123 m)
bii. Archimedes' Principle and Law of Floatation [2 marks]
1a. Tables of values
| M(g) |
W\(_1\)(g) |
W\(_2\)(g) |
W\(_3\)(g) |
U = (W\(_1\) - W\(_2\)(g) |
V = (W\(_1\) - W\(_3\)(g) |
| 5.0 |
5.00 |
4.20 |
4.70 |
0.80 |
0.30 |
| 10.0 |
10.00 |
7.90 |
8.60 |
2.10 |
1.40 |
| 15.0 |
15.00 |
12.75 |
13.50 |
2.25 |
1.50 |
| 20.0 |
17.10 |
17.10 |
16.40 |
2.90 |
3.60 |
| 25.0 |
22.10 |
22.10 |
21.40 |
2.90 |
3.60 |
S = \(\frac{y_2 - y_1}{x_2 - x_1}\) = \(\frac{3 - 0.8}{2.8 - 1.4}\) = \(\frac{11}{7}\) = 1.57.
Precaution
(i) I carefully avoided parallax error while reading the scale of the spring balance to ensure accurate measurements.
(ii) I checked and accounted for any zero error on the spring balance before taking measurements.
(iii) I handled the liquid carefully to prevent any splashing, which could lead to loss of material or inaccurate readings.
(iv) I ensured that the object did not touch the bottom or sides of the beaker to avoid interference with the force readings.
(v) I thoroughly cleaned the object (mass) before dipping it into the liquid to prevent contamination or alteration of the liquid's properties.
bii) Law of Floatation: The law of floatation states that an object will float in a fluid if its weight is equal to the weight of the fluid it displaces. For a floating object, the weight of the object is balanced by the upward buoyant force.
1a. Tables of values
| M(g) |
W\(_1\)(g) |
W\(_2\)(g) |
W\(_3\)(g) |
U = (W\(_1\) - W\(_2\)(g) |
V = (W\(_1\) - W\(_3\)(g) |
| 5.0 |
5.00 |
4.20 |
4.70 |
0.80 |
0.30 |
| 10.0 |
10.00 |
7.90 |
8.60 |
2.10 |
1.40 |
| 15.0 |
15.00 |
12.75 |
13.50 |
2.25 |
1.50 |
| 20.0 |
17.10 |
17.10 |
16.40 |
2.90 |
3.60 |
| 25.0 |
22.10 |
22.10 |
21.40 |
2.90 |
3.60 |
S = \(\frac{y_2 - y_1}{x_2 - x_1}\) = \(\frac{3 - 0.8}{2.8 - 1.4}\) = \(\frac{11}{7}\) = 1.57.
Precaution
(i) I carefully avoided parallax error while reading the scale of the spring balance to ensure accurate measurements.
(ii) I checked and accounted for any zero error on the spring balance before taking measurements.
(iii) I handled the liquid carefully to prevent any splashing, which could lead to loss of material or inaccurate readings.
(iv) I ensured that the object did not touch the bottom or sides of the beaker to avoid interference with the force readings.
(v) I thoroughly cleaned the object (mass) before dipping it into the liquid to prevent contamination or alteration of the liquid's properties.
bii) Law of Floatation: The law of floatation states that an object will float in a fluid if its weight is equal to the weight of the fluid it displaces. For a floating object, the weight of the object is balanced by the upward buoyant force.
