2019 PSLE Discussions and Strategies (Children born in 2007)

[tryourbest]

LeeTaiTai\" post_id=\"1938934\" time=\"1569904000\" user_id=\"17608:

Iluvmygals\" post_id=\"1938929\" time=\"1569903613\" user_id=\"26453:

When the ball is bouncing up....energy conversion is from kinetic to potential.....not sure how the question was asked though...

Dd says its on thr moment of ball bouce up..so kinetic + sound to potential for her.

My dd ans is the same as yr gal

[Kei]

AnxiousabtPSLE\" post_id=\"1938927\" time=\"1569903392\" user_id=\"180550:

Yes, one option was potential to kinetic and another option was potential to kinetic to sound.
Normally it should be with sound energy but since Q18 requires conversion FROM THE MOMENT THE BALL HITS THE GROUND, it should NOT have sound energy because the ball is bouncing back up.

DS said his answer is KE to SE + (elastic) PE...his reasoning is all GPE would have been converted to KE when it hit the floor, which is then converted to (elastic) PE since it’s a rubber ball...He couldn’t recall other options with KE to PE + whatever

[sweetbaby]

Kei\" post_id=\"1938941\" time=\"1569905369\" user_id=\"19442:

AnxiousabtPSLE\" post_id=\"1938927\" time=\"1569903392\" user_id=\"180550:

Yes, one option was potential to kinetic and another option was potential to kinetic to sound.
Normally it should be with sound energy but since Q18 requires conversion FROM THE MOMENT THE BALL HITS THE GROUND, it should NOT have sound energy because the ball is bouncing back up.

DS said his answer is KE to SE + (elastic) PE...his reasoning is all GPE would have been converted to KE when it hit the floor, which is then converted to (elastic) PE since it’s a rubber ball...He couldn’t recall other options with KE to PE + whatever

What are the options? thx

[sunnybear]

Anyone know the answer to question 9 MCQ talking about the flower and the coloured water. My DD answer is B & C. Correct?

[shutter]

N@rut0\" post_id=\"1938918\" time=\"1569902809\" user_id=\"181320:

AnxiousabtPSLE\" post_id=\"1938907\" time=\"1569902316\" user_id=\"180550:

So Q18 should be just potential to kinetic

I thought the moment any ball hits the ground, sound is produced. Plus, in the question, they stated that the ball bounced to a lower height. This is because some of its Kinetic Energy is lost as heat and sound energy, so i think the answer has to be KE - -> SE + GPE

My kid also select this.

[PANDAPANDA]

SAME B&C

[sunnybear]

whitecarrotcake\" post_id=\"1938925\" time=\"1569903201\" user_id=\"114080:

Paul was pushing a sofa. When Amy sat on it, he found it more difficult to push. Why is it so?
1)Gravitational force by Amy
2)Frictional force between sofa and floor
3)Frictional force between Paul and sofa
4) Potential to kinetic energy force or something

The qn is push, not lift.
More mass means more friction between floor and sofa.

So answer is (2) ? My DD put 2 as answer

[sunnybear]

shutter\" post_id=\"1938945\" time=\"1569906065\" user_id=\"5938:

N@rut0\" post_id=\"1938918\" time=\"1569902809\" user_id=\"181320:

[quote=AnxiousabtPSLE post_id=1938907 time=1569902316 user_id=180550]So Q18 should be just potential to kinetic

I thought the moment any ball hits the ground, sound is produced. Plus, in the question, they stated that the ball bounced to a lower height. This is because some of its Kinetic Energy is lost as heat and sound energy, so i think the answer has to be KE - -> SE + GPE

My kid also select this.[/quote]My DD put kinetic + sound —> potential

[itsjustmehar]

i put 2 for the spring question as they asked the elastic spring force

[itsjustmehar]

i put 2 for the spring question as they asked the elastic spring force and the extension