Magnet and Pivot Point
endorsed by University of Cambridge International Examinations
Physics for Cambridge IGCSE
Complete
seCond edition
Teacher’s Resource Kit
Ian Collins
2
PRACTICAL
Name:
2.2 Acceleration due to gravity using a ticker tape timer
Aim: To determine a value for the acceleration due to gravity, g. Equipment: n ticker tape timer n ticker tape n pulley mass n string n adhesive tape n 30 cm rule n scissors n glue n Introduction
As an object falls freely it will accelerate towards the centre of the Earth. This is due to the gravitational attraction between object and the Earth. The magnitude of this acceleration can be determined by analysing the motion of the falling mass with a ticker tape timer.
3 Record the motion of the trolley using the ticker tape timer.
Results and analysis
1 Cut, label and glue the tentick lengths side by side on the velocity–time graph on the results sheet attached. 2 Deduce the slope (gradient) of the plot.
Theory
1 The time interval between 10 dots is called a tentick length. 2 A tentick length corresponds to 0.2 seconds.
Conclusions
1 Determine a value for the acceleration due to gravity and compare this with the accepted value of 9.81 ms–2. 2 Is you value an overestimate or an underestimate? What might have caused this difference?
Method
1 Set up the apparatus as shown. mass trolley frictionless slope
frictionless pulley
slotted masses
2 Allow the falling mass to pull the tape through a ticker tape timer via the string over the pulley.
36
© OUP: this may be reproduced for class use solely for the purchaser’s institute
PRACTICAL
Name:
3.1 The principle of moments
Aim: To understand and apply the principle of moments using a lever. Equipment: n stand, boss and short metal rod to act as the fulcrum n 30 cm rigid metal strip with holes drilled and labelled every centimeter along its length to act as a balance bar n 6 × 20 g slotted or hanging masses
Introduction
The turning effect of a lever not only depends
Physics for Cambridge IGCSE
Complete
seCond edition
Teacher’s Resource Kit
Ian Collins
2
PRACTICAL
Name:
2.2 Acceleration due to gravity using a ticker tape timer
Aim: To determine a value for the acceleration due to gravity, g. Equipment: n ticker tape timer n ticker tape n pulley mass n string n adhesive tape n 30 cm rule n scissors n glue n Introduction
As an object falls freely it will accelerate towards the centre of the Earth. This is due to the gravitational attraction between object and the Earth. The magnitude of this acceleration can be determined by analysing the motion of the falling mass with a ticker tape timer.
3 Record the motion of the trolley using the ticker tape timer.
Results and analysis
1 Cut, label and glue the tentick lengths side by side on the velocity–time graph on the results sheet attached. 2 Deduce the slope (gradient) of the plot.
Theory
1 The time interval between 10 dots is called a tentick length. 2 A tentick length corresponds to 0.2 seconds.
Conclusions
1 Determine a value for the acceleration due to gravity and compare this with the accepted value of 9.81 ms–2. 2 Is you value an overestimate or an underestimate? What might have caused this difference?
Method
1 Set up the apparatus as shown. mass trolley frictionless slope
frictionless pulley
slotted masses
2 Allow the falling mass to pull the tape through a ticker tape timer via the string over the pulley.
36
© OUP: this may be reproduced for class use solely for the purchaser’s institute
PRACTICAL
Name:
3.1 The principle of moments
Aim: To understand and apply the principle of moments using a lever. Equipment: n stand, boss and short metal rod to act as the fulcrum n 30 cm rigid metal strip with holes drilled and labelled every centimeter along its length to act as a balance bar n 6 × 20 g slotted or hanging masses
Introduction
The turning effect of a lever not only depends