A Jalan Sultan parent considering weekday or weekend Primary 6 PSLE Science tuition may hear a child explain a bouncing ball this way: “Gravity gives it energy as it falls, then the missing energy is destroyed every time it hits the ground.” A better explanation begins with the ball’s raised position, where it has gravitational potential energy. As it falls, some energy is converted into kinetic energy. During impact and rebound, energy can be temporarily stored through deformation and transferred to sound, thermal energy and the surroundings.
Under ordinary passive conditions a ball often does not bounce as high as its original release height. That does not prove energy has vanished; it shows that not all of the initial mechanical energy returns as the ball’s gravitational potential energy at the next highest point. A fresh paper record comparing drop height, rebound height and the changes during impact can test whether the child understands conservation rather than a slogan.
For families around Jalan Sultan, Kampong Glam and Beach Road, eduKateSG’s premium three-pax Science lessons allow each pupil to explain the stages independently. Weekday and weekend tuition should account for school fatigue, homework, travel and rest. This is a fictional paper-only comparison, not a request to drop objects from balconies, onto roads or near people; a street-titled guide does not establish a teaching room or available class.
eduKateSG · Primary 6 PSLE Science · Jalan Sultan
A bouncing ball exchanges gravitational potential and kinetic energy and transfers some energy to sound, thermal energy and deformation. A lower bounce is not energy disappearing.
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Begin with the student’s first explanation on a marked paper, rather than selecting a lesson day on instinct. Five two-chapter routes organise the ten original chapters, worked Science evidence, a changed independent check and weekday-versus-weekend family planning. The goal is a new explanation the learner can make without looking at the tutor’s solved example.
Full chapter index · Independent check · Programme information
Full chapter index
Chapters 1–5: diagnose, understand, apply and compare
1. Ask which stage the child thinks contains the missing energy
2. Explain the energy pathway from a raised ball to a rebound
3. Read three rebound peaks from one constructed ball record
4. Use weekday tuition to repair a newly marked energy statement
5. Use weekend tuition for a complete conversion-and-transfer comparison
Chapters 6–10: repair, retest, review and plan
6. Repair the disappearing-energy claim without an opposite absolute
7. Try a different rebound record without the original height
8. Judge weekday and weekend tuition by a fresh energy explanation
9. Questions families ask about energy when balls bounce
10. Bring the first energy diagram and a different rebound record
CHAPTER 1 OF 10 · Identify the energy-vanishes-on-impact claim
1. Ask which stage the child thinks contains the missing energy
A pupil watches a ball bounce progressively lower and infers that energy was destroyed by the ground at each impact. The first diagnostic question is where the ball’s energy came from before it was released. If somebody lifted it to a height, energy was supplied during lifting and associated with its position in Earth’s gravitational field. The falling movement is not a spontaneous creation of energy.
Another learner may know gravitational potential and kinetic energy but say the ball has only one form at every instant, even while it is deforming during impact. The ball and surface may temporarily store some energy in deformation, while other transfers occur. These stages can overlap and are not perfectly isolated boxes into which all the energy must fit at once.
Bring the original marked question and the child’s explanation about the lower rebound. A tutor should distinguish a weak grasp of energy forms, confusion between force and movement, and the claim that lost visible bounce height means destroyed energy. Identifying the specific missing link makes the next lesson more effective than assigning a general energy-conversion pack.
CHAPTER 2 OF 10 · Identify the energy-vanishes-on-impact claim
2. Explain the energy pathway from a raised ball to a rebound
A ball held above the floor has gravitational potential energy due to its position. When released, it accelerates downward under gravity in the ordinary model, and potential energy can be converted into kinetic energy of motion. Near impact, some of the ball’s kinetic energy goes into deformation of the ball and surface; an elastic restoring effect can contribute to the rebound.
Not all energy necessarily returns as useful upward motion. During impact and movement, energy can be transferred into thermal energy in the ball, surface and air, as well as sound. Some mechanical energy may also be transferred into movement of the surface or other objects. When the ball reaches the highest point of its rebound, its gravitational potential energy is lower if the peak height is below the original release height.
The Primary 6 task should not be expanded into advanced coefficient-of-restitution formulas unless a particular school question requires them. The essential Science account identifies relevant forms, follows transfers and uses conservation correctly. Lower measured height is evidence about the returned mechanical energy, not proof that the total energy of the world has been reduced.
CHAPTER 3 OF 10 · Follow potential, kinetic and deformation stages
3. Read three rebound peaks from one constructed ball record
Imagine a hypothetical paper record showing a ball released from 100 cm above a firm, level floor with no extra pushes. The first rebound reaches a peak of 62 cm above the same floor, and the second rebound reaches 37 cm. The record keeps the same ball, reference floor and general conditions. No detailed force, sound or temperature measurements are supplied.
The observed peak heights decrease from 100 cm to 62 cm and then to 37 cm. Under these passive conditions, the ball recovers less gravitational potential energy at each listed rebound peak than it had at the earlier release height. The decrease is consistent with energy being transferred into other forms and surroundings through the motion and collisions. It does not imply that some energy ceased to exist.
The paper table is an illustration rather than a measured set of physical bounce trials. It does not give enough information to calculate exact thermal-energy transfers or determine the fraction that became sound. A student should avoid assigning invented percentages or claiming that the ball never changes shape at impact simply because the picture only shows its positions above the floor.
| Illustrative one-ball record | Height above same stationary floor | Relevant school-level interpretation |
|---|---|---|
| Before release | 100 cm | Gravitational potential energy due to raised position |
| While falling | Decreasing height | Potential energy can convert into kinetic energy |
| First rebound peak | 62 cm | Less gravitational potential than at 100 cm |
| Second rebound peak | 37 cm | Less gravitational potential than at 62 cm |
| At impacts | Deformation and other interactions | Energy transfers include sound, warmth and surroundings |
CHAPTER 4 OF 10 · Follow potential, kinetic and deformation stages
4. Use weekday tuition to repair a newly marked energy statement
A weekday lesson can respond promptly to a returned Primary 6 Energy Conversion question. The student may remember why they wrote that the missing energy disappeared. The tutor can begin with the raised ball, trace its downward kinetic energy and identify the sound and warmth associated with an imperfect collision. A carefully sequenced explanation repairs the original inference.
After a long school day, a complicated graph of every bounce might overwhelm a child who has not yet connected position with energy. Start with the first release and one rebound: the initial peak is higher than the next. Ask which energy form corresponds to a raised position and why the next peak is lower when transfers to the surroundings occur.
Leave a changed record for another day, perhaps with a different drop height and first rebound, but without the same pictures. The pupil should explain why the rebound peak is lower without saying energy was annihilated. A correct fresh sentence after a delay is stronger evidence than an immediate recital of the teacher’s arrows.
CHAPTER 5 OF 10 · Read a controlled three-bounce height record
5. Use weekend tuition for a complete conversion-and-transfer comparison
A weekend session may allow more time to examine four moments: before release, while falling, briefly during contact with the floor, and at the rebound peak. The tutor can ask which energy form is especially relevant at each point, and why the collision stage involves more than simply switching kinetic energy back into gravitational potential energy instantly.
Students can consider how the same ball might behave on different surfaces, such as a hard smooth floor and a soft deformable mat, with all other relevant conditions controlled. Surface properties affect how energy is stored and dissipated during contact; however, a strong prediction about the exact rebound height would require the specific materials and observed record. An elastic-sounding word alone is not a numerical measurement.
Keep the lesson paper-based and safe. No objects need to be dropped from height for the parent to explain the mechanism. A short weekday retest with a changed ball or surface gives useful evidence of transfer while preserving ordinary weekend family time and the student’s recovery.
CHAPTER 6 OF 10 · Read a controlled three-bounce height record
6. Repair the disappearing-energy claim without an opposite absolute
The original false rule is that every lower bounce destroys the missing energy. Conservation tells us energy is transferred and converted, not annihilated. But replacing it with “every ball always bounces lower” is too absolute: an object could receive additional energy from a moving surface or another external input, and outcomes depend on conditions. In this passive no-extra-input model, lower rebound peaks are the observed result.
Another shortcut is that all the difference between the two peaks must have become sound. Collisions can transfer energy to many forms and places, including warmth, deformation, air motion and the floor. Without measurements of those pathways, a pupil should name reasonable transfers but not invent an exact breakdown. The scientific statement remains faithful to what the diagram actually supplies.
In a three-pax class, one learner can identify gravitational potential energy, another kinetic energy during descent, and the third the transfers and temporary deformation during impact. Afterwards every pupil should write the whole pathway for a changed ball record alone. The shared discussion prepares the reasoning; the new independent response proves whether it has become each child’s own method.
CHAPTER 7 OF 10 · Try a changed ball-and-surface question
7. Try a different rebound record without the original height
Cover the 100–62–37 cm table. The independent check describes another ball raised to 90 cm above a stationary floor and released without extra input, after which it rebounds to a peak of 48 cm. The pupil must explain why a lower return height is compatible with conservation of energy and name at least two destinations or forms of transferred energy.
A strong answer begins with gravitational potential energy at the 90 cm position and kinetic energy as the ball falls. At impact some of the energy is involved in temporary deformation and motion changes, and some transfers into sound, thermal energy or surrounding objects. The new rebound has less gravitational potential energy at 48 cm than at 90 cm, but the total energy has not vanished.
At another delayed retest, change the surface but do not provide a rebound measurement. Ask whether a precise new height can be determined from the words soft or hard alone. A careful learner should explain the possible role of material and deformation while recognising the limits of the evidence.
Independent check
A ball is raised to 90 cm above a stationary floor and released without any new push. Its first rebound reaches only 48 cm. A pupil says the missing energy was destroyed and that the ball cannot have had any potential energy before it moved. Correct both claims and name two kinds of energy transfer associated with impact.
Checking notes
The ball had gravitational potential energy at its raised position. During falling, some of it converted into kinetic energy; during impact and rebound, energy was temporarily involved in deformation and transferred into other forms or surroundings, including sound and thermal energy. The lower 48 cm peak shows less returned gravitational potential energy, not destruction of energy.
CHAPTER 8 OF 10 · Try a changed ball-and-surface question
8. Judge weekday and weekend tuition by a fresh energy explanation
Weekday tuition can repair a marked energy-conservation misconception while the student’s first answer is familiar. Weekend tuition can give more room for a multi-stage conversion account and an examination of where the energy goes. Either can work if the pupil has sufficient attention and a later opportunity to explain a new passive-bounce scenario independently.
Parents can check four progress markers: the child links height with gravitational potential energy, recognises kinetic energy during motion, identifies possible transfers at impact and avoids claiming that lower rebound height means energy was destroyed. A fifth check is respecting the limits of a height-only record instead of inventing exact sound or heat percentages.
Jalan Sultan families should ask for the actual teaching location, group timing, travel and fees before deciding. The neighbourhood title does not promise a class there. A good lesson rhythm makes room for school and rest while leaving a short independent retest that reveals whether the important idea survived.
| Parent planning question | Weekday possibility | Weekend possibility |
|---|---|---|
| Fresh returned Energy question | Correct the missing-energy claim promptly | Compare position, descent and impact stages carefully |
| Scientific mechanism | Trace potential energy into motion | Discuss deformation, sound and thermal transfers |
| Delayed independent return | New 90 cm rebound record another day | Brief weekday bounce question after weekend lesson |
| Success standard | No energy-destruction claim | Explains changed height record without invented percentages |
CHAPTER 9 OF 10 · Plan PSLE revision from an independent energy pathway
9. Questions families ask about energy when balls bounce
Does a ball contain gravitational potential energy before it is dropped? Yes. In the simple Earth-and-ball model, a ball at a raised position has gravitational potential energy associated with its height.
Why is a later rebound often lower? Not all of the earlier mechanical energy returns as upward motion. Transfers into deformation, sound, warmth and surroundings can reduce the ball’s subsequent rebound height.
Does the lost bounce height mean energy disappeared? No. Energy has been transferred or converted. Height data alone do not tell us the exact amounts transferred into each form.
Why does height matter for potential energy? For the same object near Earth, raising it increases its gravitational potential energy relative to a chosen lower reference.
What happens during impact? The ball and surface deform and energy can be temporarily stored and transferred in several forms.
Does a lower second bounce mean a conservation law failed? No. Mechanical energy has been transferred into other forms and surroundings.
CHAPTER 10 OF 10 · Plan PSLE revision from an independent energy pathway
10. Bring the first energy diagram and a different rebound record
Bring the pupil’s marked Primary 6 Science Energy Conversion question, including the reason they offered for the lower bounce. A tutor can identify whether the difficulty is recognising gravitational potential energy, tracing kinetic energy, describing impact or respecting conservation in the account of transferred energy.
In a premium three-pax lesson, each pupil should explain a stage and independently solve a new height record after a short delay. Parents can compare that fresh response with the original claim instead of assuming that a completed worksheet means the misconception has vanished.
Visit eduKateSG Primary 6 PSLE Science tuition to discuss programme arrangements. Confirm the learner’s course and current school chapter, then the actual venue and weekday or weekend availability before enrolment.
Chapter index ↑ · Previous chapter · Programme information →
This lesson applies Primary 6 Standard Science Energy Conversion and its link with gravitational and elastic spring forces. Specialist collision coefficients and numerical energy formulas are not required. For distinct related conversions see Primary 6 Science | Arab Street on stored potential energy in a wind-up toy, and Victoria Street on electrical energy in a fan.
Curriculum reference: MOE Primary Science Teaching & Learning Syllabus, updated May 2024. The paper diagrams, descriptions and numerical records are constructed educational examples, not actual laboratory measurements or guaranteed examination outcomes. Verify the child’s current class topic and Standard or Foundation Science expectations.
For the larger schedule decision, read eduKateSG’s weekday-versus-weekend Science learning-rhythm guide. Jalan Sultan is the intended locality, not a claimed classroom at that street. Confirm actual tuition venue, group availability, price and journey before enrolling.