Thank you for your time.
The appropriate answers are 1) Increase the height of the metal stand holding the ball 2)Use a heavier metal ball.

But, how about moving the fulcrum closer to the wooden disc?Does using a higher fulcrum or a lighter wooden disc help?Please help to explain.

Hi there,

Sorry this took a little longer to respond. I believe the various options would include:
1) increase the height of the metal stand;
2) increase the size of the metal ball;
3) moving the fulcrum and/or increasing its size;
4) changing the wooden disc; or
5) changing the length of the wooden plank.

Personally, I would opt for 1) or 2). Choosing 3) or 5) could lead to unpredictable results. For example if I move the position of the fulcrum, the angle in which the wooden disc leaves the wooden plank will change - potentially missing the drum altogether. Option 4 should achieve the desired result however it may alter the 'dome' sound required.

Hi Chris
Thank you, a good answer is always worth waiting for.

For PSLE science, I think option 1 and 2 are the most appropriate answers. Students are taught that increase in height and mass would lead to higher GPE.

3) Moving the fulcrum towards the wooden disc.
From the law of conservation of energy, it may not help as we are still experiencing the same PE at the initial stage. However from the principle of moment, the same force acting from a longer effort arm would be able to balance a higher load because of a shorter load arm. I am not sure if it would cause the wooden disc to fly a longer distance.(still figuring out why)
From simple machines in P5, students are taught that moving the fulcrum towards a load leads to a lesser effort.

3) and/or increasing its size;
Increase the size of a fulcrum may lead to a lower PE at the initial stage as the wooden plank is tilted higher towards the ball.

4) Changing the wooden disc; or
A lighter wooden disc may fly longer, but the sound may be different magnitude.

5) Changing the length of the wooden plank.
Same as option 3.

Once again, Thank you.

Thanks for sharing your thoughts on this. Good questions and equally good answers.

c

Hi Chris
PSLE students learn that a lesser effort is required to lift the same load when the fulcrum is moved nearer to the load. In this question, moving the fulcrum towards the wooden disc means the same effort (same ball dropping from the same height) can lift a heavier load. To put in another way, the wooden block is now thrown with a greater force.

I am just wondering if there are any formulae in Physics to substantiate the above explanation. I know this is beyond PSLE Science, just to satisfy my curiosity and to confirm that the above scenario is right.