experiment in inertia (undone)

1. Inertia:
Diagram 3.1 shows two wooden tops. One of the tops is partly coated with tin. Both tops
are the same size and are rotated with the same velocity.
a) Inference:
The time taken for the body to stop spinning is influenced by the mass
b) Hypothesis:
The bigger the mass is, the longer the body will spin
1) Aim
To investigate the relationship between mass and period of
oscillation
2) Variables
i) Manipulated Variable: The mass of the plasticine
ii) Responding Variable : The period of oscillation
iii) Constant Variable: The number of oscillation
3) Apparatus and
Materials
Hacksaw blade, stopwatch, plasticine, G-clamp
Diagram
Procedure
1) The hacksaw blade is clamped horizontally.
2) Plasticine with a mass of 50 g is clamped to the end of the
hacksaw blade.
3) The blade is displaced horizontally and released, and a
stopwatch is started simultaneously.
4) The time taken for 20 complete oscillations is recorded.
5) The period of oscillation is calculated.
6) Repeat the experiment at least 4 times.
7) Repeat the previous steps, but change the mass of the
plasticine to 100g, 150g, 200g and 250g.
Tabulation of data
Mass of
plasticine
m/g
Time for 20 oscillations, t20/s Period of
oscillation,T
T=t20/sT1 T2 average
50
100
150
200
250

2. Period
Analysis of data
Mass

3. The Effect Of Force
Diagram shows a man pushing a broken-down car with passengers in it. The car moves with
a small acceleration and another man pushing the same car with the same force with no
passenger in it. The car moves with a bigger acceleration.
a) Inference
Acceleration of the car depends on the mass
b) Hypothesis
The bigger the mass, the lower the acceleration.
Aim
To investigate the relationship between the mass and the acceleration
of the trolley
Variables
i) Manipulated Variable: Mass
ii) Responding Variable: Acceleration
iii) Constant Variable: Force
Apparatus and
Materials
Ticker tape, ruler, string chord, pulley, power supply, trolley, ticker
timer, connecting wire, friction compensated inclined plane, slotted
weight, wooden blocks and metre rule
Diagram
Procedure
1) The apparatus is set up as shown in the diagram.
2) A wooden block of 0.2 kg is added on the trolley
3) Power supply is switched on and the trolley is being pulled by the
weight.
4) Based on the ticker tape obtained, the acceleration of the trolley is
calculated by using the formula.
5) The experiment is repeated by using wooden blocks of 0.4kg,
0.6kg, 0.8kg and 1.0kg.
Tabulation of
data Mass,m (kg) Acceleration, a (m s-2)
0.2
0.4
0.6
0.8
1.0

4. Analysis of Data
Period
Mass

5. Elasticity
Diagram 3.1 shows a worker carrying a gas tank. Diagram 3.2 shows the same worker
carrying two gas tank.
Observe the length of the spring in the suspension system of the motorcycle in both
situations. Based the observation:
Inference
The compression of a spring changes when the force applied changes.
Hypothesis
The extension of a spring increases when the applied force increases.
Aim To investigate the relationship between the force applied, F, and the
extension, x, of a spring.
Variables i) Manipulated Variable: The force applied, F
ii) Responding Variable: The extension of the spring, x
iii) Constant Variable: The type of spring
Apparatus and
Materials
Spring, slotted weights, retort stand with clamp, metre rule, pin and
plasticine
Diagram
Procedure 1) The apparatus is set up as shown.
2) With no slotted weights attached to the spring, the initial position
of the pin is recorded as X0.
3) A slotted weight of m=40g is attached to the end of the spring.
4) The new position of the extension of spring, x’ of the pin is
recorded.
5) The extension of the spring is calculated as x = x’ - x0
6) Steps 3 and 4 are repeated using m= 60g, 80g, 100g and 120g.
Force, F (Mass)/g Length of the spring,
x’/cm
Extension
x = x’ – x0/cm
40
60
80
100
120

6. Analysis of Data
Force, F
Extension, x