Lower Secondary Science
-
Yishun:
Assessment Books for Sec 1:My DD is in Sec 1 this year in Express stream. They do not have any Science Text book cos their school provide them with Science note. But I still would like her to do some Science Assessment during her free time.
Anyone can recommend me any which assessment to purchase.
Thanks in advance.
1. Title: \"Lower Secondary Science Conceptual Exercises\" Author: G.S. Cheng, Publisher:GLM. The book is Red in Color. I have used it for several years with my classes and it is generally good.
2. Title:\"Comprehensive Guide Lower Secondary Science A&B\", Author: David Lim, Publisher: Wiseman. This one has both notes and questions.
Textbook for Sec 1:
\"Interactive Science for Inquiring Minds\" (Vol 1 and 2), Author Tho Lai Hoong et al. Publisher: EPB.
For those students who have a phobia of textbooks, another option is a book in Kinokuniya called \"What's Science All About?\" Publisher: Usborne. It is good for the Sec 1 level and it covers a lot of the material in the Lower Sec syllabus for Bio, Chem and Physics. But it has lots of pictures and looks like a regular book rather than a textbook. Any book that can capture their interest and get them reading and thinking about science on their own would be a huge plus at this age.
If any student wants to go on to University or get a higher paying job in any science, medical or engineering field, then they really should be able to read science books at the secondary level and develop good reading comprehension for the sciences. -
:thankyou:
Dr.Daniel:
Assessment Books for Sec 1:Yishun:
My DD is in Sec 1 this year in Express stream. They do not have any Science Text book cos their school provide them with Science note. But I still would like her to do some Science Assessment during her free time.
Anyone can recommend me any which assessment to purchase.
Thanks in advance.
1. Title: \"Lower Secondary Science Conceptual Exercises\" Author: G.S. Cheng, Publisher:GLM. The book is Red in Color. I have used it for several years with my classes and it is generally good.
2. Title:\"Comprehensive Guide Lower Secondary Science A&B\", Author: David Lim, Publisher: Wiseman. This one has both notes and questions.
Textbook for Sec 1:
\"Interactive Science for Inquiring Minds\" (Vol 1 and 2), Author Tho Lai Hoong et al. Publisher: EPB.
For those students who have a phobia of textbooks, another option is a book in Kinokuniya called \"What's Science All About?\" Publisher: Usborne. It is good for the Sec 1 level and it covers a lot of the material in the Lower Sec syllabus for Bio, Chem and Physics. But it has lots of pictures and looks like a regular book rather than a textbook. Any book that can capture their interest and get them reading and thinking about science on their own would be a huge plus at this age.
If any student wants to go on to University or get a higher paying job in any science, medical or engineering field, then they really should be able to read science books at the secondary level and develop good reading comprehension for the sciences.
:thankyou: Dr. Daniel,
Appreciate your great help. -
These skills in using the calculator fx-96 SG PLUS are useful to check your answers in O level Amaths and Emaths:
1.\tRound off to number of decimal places (Fix)
2.\tRound off to number of significant digits (Sci)
3.\tUsing the memory A, B, C, D, E, X, Y to store the answers for intermediate steps so the final answer is accurate
4.\tUsing statistics mode to calculate the mean and standard deviation (for both grouped and ungrouped data)
5.\tUsing statistics mode A+BX linear regression to calculate the intercept and gradient of transformed linear graph. ( When keying in the data, do not key in the data that you ignored in your graph plotting)
6.\tUsing DRG to convert between radians and degrees
7.\tUsing fraction to determine Highest Common Factor
8.\tSolving simultaneous linear equations of 2 to 3 unknowns, quadratic and cubic equations of 1 unknown
9.\tFinding the gradient of a curve with known equation without differentiating, or checking the differentiation results by substituting a small number such as 0.001 as delta x.
Gradient or dy/dx = [f(x+ delta x)- f(x)]/ (delta x)
Eg. Find the gradient of the curve for y = (2x^2 ā 1/x) at x=3
Find y at x= 3.001. Call it f(b)
Find y at x = 3. Call it f(a)
Gradient at x = 3 = [f(b)- f(a)] / 0.001 -
How much is this?
-
f(b) = 2 X 3.001^2 - 1/3.001 = 17.6788
f(a) = 2 X 3 ^2 - 1/3 = 17.6667
[f(b)-f(a)] / 0.001 = 12.1 (3 sig fig)
Compared with differentiation
dy/dx = 4x + 1/x^2
gradient at x= 3, = 109/9 = 12.1 (3 sig fig)
For Emaths students who have not learnt differentiation, the calculator approach is an alternative way to check the gradient. -
Hi ....
My dd is rather confused about work done. It says in her text book that work done on an object is force exerted on the object multiply by the distance moved by the object in the same direction.
Case study :
A student lifts a box weighing 50N thru a vertical height 1.1m and then walks horizontally for 2 m while holding the box. What is the work done by the student?
Workdone on the box being lifted = F x d
= 50N x 1.1m = 55J
As for horizontal movement, according to the text bk, the horizontal force is zero. So work done horizontally is also zero.
My question: The fact that the student pushes himself forward to overcome frictional force when walking means that there is force and therefore work is done horizontally. Unless the text book means horizontally no work is done on the box (which they did not make clear)???
Can I clarify that horizontally there is still work done by the walking motion but this has no bearing on the work done on the box?
Also, I know the unit for workdone is Joules. But is it wrong to put the unit as Nm? -
Verysuperkiasu:
For your last question, it is better to express energy as Joules. As a side note, the unit of moment is Nm, which is not written as Joules since in the case of moments, the force is perpendicular to the distance from the fulcrum.Hi ....
My dd is rather confused about work done. It says in her text book that work done on an object is force exerted on the object multiply by the distance moved by the object in the same direction.
Case study :
A student lifts a box weighing 50N thru a vertical height 1.1m and then walks horizontally for 2 m while holding the box. What is the work done by the student?
Workdone on the box being lifted = F x d
= 50N x 1.1m = 55J
As for horizontal movement, according to the text bk, the horizontal force is zero. So work done horizontally is also zero.
My question: The fact that the student pushes himself forward to overcome frictional force when walking means that there is force and therefore work is done horizontally. Unless the text book means horizontally no work is done on the box (which they did not make clear)???
Can I clarify that horizontally there is still work done by the walking motion but this has no bearing on the work done on the box?
Also, I know the unit for workdone is Joules. But is it wrong to put the unit as Nm?
I agree with you that question could be phrased better. It's clearer to talk about work done on the box. If the student is walking horizontally at constant velocity, then we could argue there is no net force on the box in the horizontal direction. Just thinking about the box itself, it is moving at a constant velocity horizontally. If air friction is negligible, then you could say that horizontally the student does not need to exert a force on the box so long as he is walking at constant velocity as he lifts the box.
The main point of the question is that a vertical lifting force cannot account for work in the horizontal direction. For work, force must be in the same direction as the motion.
Another other version of this problem is luggage on a conveyor belt being lifted up and moved horizontally into the luggage compartment of an airplane. Think of luggage on a slanted incline conveyor belt. That's another case where moving the luggage up requires work, but if it moves horizontally at constant velocity with no friction opposing the motion, then there is no work in the horizontal direction.
And yes you are right about the idea if you have to exert a force on yourself while walking to maintain a constant speed then yes you are doing work in the horizontal direction. The faster you walk or run the more air friction there will be and the more force and work you would need.
So as a student answering a structured question like this, you could write \"assuming no horizontal force on the box\"... and then write your solution. -
Dr.Daniel:
Thank you very much, Dr Daniel....for the clarification.
For your last question, it is better to express energy as Joules. As a side note, the unit of moment is Nm, which is not written as Joules since in the case of moments, the force is perpendicular to the distance from the fulcrum.
I agree with you that question could be phrased better. It's clearer to talk about work done on the box. If the student is walking horizontally at constant velocity, then we could argue there is no net force on the box in the horizontal direction. Just thinking about the box itself, it is moving at a constant velocity horizontally. If air friction is negligible, then you could say that horizontally the student does not need to exert a force on the box so long as he is walking at constant velocity as he lifts the box.
The main point of the question is that a vertical lifting force cannot account for work in the horizontal direction. For work, force must be in the same direction as the motion.
Another other version of this problem is luggage on a conveyor belt being lifted up and moved horizontally into the luggage compartment of an airplane. Think of luggage on a slanted incline conveyor belt. That's another case where moving the luggage up requires work, but if it moves horizontally at constant velocity with no friction opposing the motion, then there is no work in the horizontal direction.
And yes you are right about the idea if you have to exert a force on yourself while walking to maintain a constant speed then yes you are doing work in the horizontal direction. The faster you walk or run the more air friction there will be and the more force and work you would need.
So as a student answering a structured question like this, you could write \"assuming no horizontal force on the box\"... and then write your solution.
-
Hi, Dr Daniel
Do you have any recommendation for sec 2 sci assessment book. -
DJ123:
Yes the book that I recommend is called \"Lower Secondary Science Conceptual Exercises\" author: G.S. Cheng. It is red in colour and the publisher is GLM.Hi, Dr Daniel
Do you have any recommendation for sec 2 sci assessment book.
This is good for many but not all students in the express stream. If the school has a challenging express syllabus, or if the student is on an IP or IB track, then my strategy is to make sure they master the level in this book first and then I move them on to Sec 3 level books and worksheets that I have.
Hello! It looks like you're interested in this conversation, but you don't have an account yet.
Getting fed up of having to scroll through the same posts each visit? When you register for an account, you'll always come back to exactly where you were before, and choose to be notified of new replies (either via email, or push notification). You'll also be able to save bookmarks and upvote posts to show your appreciation to other community members.
With your input, this post could be even better š
Register Login