Archive | November, 2012

Question from P6 Student

17 Nov

Q. Adam and Eve took 49 hours to complete their art project, working separately on their own.
If Adam had worked 5 fewer hours and Eve had worked 6 more hours,
Adam would have put in 2 hours more than Eve.
How many hours did Adam work on the project?

Please click the following link for suggested solution: Question from P6 Student

A Heartwarming Note from a Parent

15 Nov

A parent sent a Thank-You note to one of our trainers.

Students also wrote in their thoughts and feelings about trainers who have been coaching them this entire semester:

Question from Weekly Prized Science Hub Challenge (12 November)

12 Nov

Closing Date: 25 November 2012

Since young, Rayne has a big interest in automotive. He loves collecting various types of car miniatures, starting from racing cars, luxury cars, ambulances, and even military tanks.

To satisfy his interest, his parents brought him to visit their relative who works in an automobile service centre.

While walking around the place, Rayne found a lot of unused bald tyres in one corner.

Motivated by his curiosity, he asked an uncle, “Why were those tyres dumped?”

The uncle explained, “The bald tyres are not safe to be used. Hence, they must be changed regularly with new grooved tyres.”

(a) From scientific views, explain why the grooved tyres are safer to be used compared to the bald tyres (despite of the fact that both tyres are made of the same materials, have the same mass, and have the same volume of air).

(b)  While looking around the factory, Rayne was reminded of how the tyres of military tank are designed differently from the ones of racing cars. The tyres are bundled by sheets of metal.  Based on your knowledge about material, explain why metal is used.

CRITERIA OF ASSESSMENT :

1. Hit the right keywords

2. Phrase the answers correctly

SUBMISSION :

1. Send your answer through PRIVATE FACEBOOK MESSAGE to Science Hub. The link : Science Hub on Facebook

2. Email your answer in the form of MS Word / PDF file to devi@sciencehub.com.sg by November 25th!

Questions from students (Lesson on 1st Nov)

2 Nov

P3 Question

Q1.

Mr Silly had a yarn which was 208 cm long. He used the string to form 4 squares. What is the length of 6 identical squares?

Please click the following link for the solution: P3 Question (1 Nov)

P5 Questions

Q1.

The ratio of the number of apple trees to the mango trees is 7 : 1.  When 28 apple trees are chopped down to give space for 18 mango trees, there are 8 more apple trees than mango trees.  How many mango trees are there at first?

Q2.

Team A has more tickets than Team B. Each team sold 1/2 of their tickets. In the end, Team A has 480 more tickets than Team B. How many more tickets does Team A have at first?

Q3.

Given that A and B are identical squares, and D has an area of 128 cm2, find the area of the whole figure.

Please click the following link for the solutions to these three P5 questions:

P5 Questions (1 Nov)

2012 Year End Holiday Programme Highlights

1 Nov

Our Year End Holiday program (Part III) has started!

December 17-21

Dear Parents,

Time flies. Days pass us by quickly. The holidays are almost upon us again. This means, it is time for fun and joy for our precious ones!

We are excited to invite you to participate in our Year End Holiday Programme. As always, our holiday programme is designed to bring passion in learning, inspiration in achieving, …….to your child.

PSLE A* Achievers / P6 Problem Solving Heuristics
This course is a head-start class for P5 pupils going to P6 next year. Before the busy P6 year begins, they can start to learn skills to handle higher-order challenging problems during the holidays.

SMOPS
This programme is designed to enhance Math Olympiad skills in pupils who are keen in taking part in the Singapore Mathematical Olympiad for Primary Schools (SMOPS) competition at the age of 12. This competition is organised by Hwa Chong Institution.

IQ Maths
This programme is meant for the younger ones (ages 6 – 8) to acquire numerical skills in a fun and lively way. We have IQ quizzes to enhance pupils’ Mathematical intelligence and flexibility in thinking; hands-on activities to make math concrete and realistic, to understand geometric shapes and handle computations.

MOT
Mathematical Olympiad Training programme (MOT Level 1, 2 and 3) is for pupils going to P2 and P3 in 2013. This class builds the pupils up in their foundation in Math Olympiad topics and eventually they will have the necessary skills to tackle Math Olympiad questions.

Science Programme
Science classes are available for both Primary and Secondary levels. Our strength is in the content and delivery of the lessons in an engaging manner. Hands-on experiments will be carried out during holidays to build up pupils ’experimental knowledge.

Do check out course schedules for Part III of our Year End Holiday Program (17 – 21 December 2012) at the following branches:

Interested to sign up for school term classes? Take a look at our course schedules for Semester 1 in 2013 too!

Enquiries? Feel free to contact us.

Question from Ethan

1 Nov

Q.

The average number of sit-ups performed by 15 girls and some boys was 50.
The average number of sit-ups performed by the girls was 80% of the average number of sit-ups performed by all the pupils.
The average number of sit-ups performed by the boys was 30% more than the average number of sit-ups performed by the girls.

(a) What was the average number of sit-ups performed by the girls?
(b) What percentage of the pupils were boys?

Please click the following for suggested solution: Question from Ethan

Solution to Weekly Prized Science Hub Challenge (19 October)

1 Nov

As a kitchen utensil specialist in IQEA, Lily intends to create a cooking pot which is able to cook food at a rapid rate. She then investigates two cooking pots made of the same material. She puts water and a piece of carrot into the pots, covers them with lids, and turns on the stove.

Image

(a) Besides material of the cooking pots, which other variables should be kept constant to ensure the fairness of this experiment? Give 5 options.

ANSWER

Quote:
1. The volume of water (which is sufficient to cover the carrot)
2. The mass of carrot
3. The temperature of stove
4. The length of metal plate of stove
5. The thickness of pot

(b) Based on your hypothesis, which carrot would be cooked at a faster rate? Explain why.

ANSWER

Quote:
Carrot in Set-Up B would be cooked the fastest.
The reason is because the base of cooking pot B provides greater surface area in direct contact with metal plate of the stove. It allows cooking pot B to gain heat from the stove the fastest and helps the carrot to be cooked the fastest.

EXPLANATION

Quote:

Set-Up A has lesser surface area in direct contact with the stove due to the presence of gapson its base.

Image

COMMON MISTAKE

Quote:

Set-Up B has more surface area than Set-Up A.

:idea: Set-up B has less exposed surface area to the heat than Set-Up A does. But it has more surface area in direct contact with the stove compared to Set-Up A.

(c) However, after a while, Lily finds out that the carrots from both setups are still half-cooked. Besides increasing the hotness of stove, what can she do to increase the rate of cooking? Explain.

ANSWER #1

Quote:
By keeping the mass of carrot from each setup constant, she can chop off the carrots into smaller pieces. It aims to increase the exposed surface area of carrot with the surrounding boiling water. Thus, heat from water can be gained faster to increase the rate of carrots’ cooking.

EXPLANATION

Quote:

The differences between “surface area in direct contact with” and“exposed surface area” are :

Image

Image

ANSWER #2

Quote:
She can either use a pot which is made of better conductor of heat oruse a thinner pot. Hence, heat can be transferred from the stove to the water and carrot at a faster rate, allowing the carrot to be cooked faster.

COMMON MISTAKE

Quote:

In daily life, decreasing the volume of water may help to increase the temperature of water at a faster rate, allowing the carrot to be cooked in a shorter duration of time.

However, in this case the carrot is just nicely submerged in the water (look at the diagram above)Reducing the volume of water may not soak the carrot completely. Although the water boils faster, the carrot will not be cooked evenly.

If you need more assistance in solving the questions, please feel free to either send a private message or to post in our Facebook page: Science Hub on Facebook