Sunday, November 15, 2015

2015 O level Science Chemistry 5076/ 5078 Paper 1 (MCQ) Suggested Answers

Dear students, the answers to the 2015 O level Science Chemistry 5076/ 5078 Paper 1 (MCQ) are shown below. All solutions/ answers are provided by teachers of Penciltutor School and the Singapore MOE or UCLES bears no responsibility for these suggested solutions/ answers. As usual, if you find any errors in our solutions or if you need an explanation, kindly send an email to admin@penciltutor.com.


2015 O level Science Physics 5076/ 5077 Paper 1 (MCQ) Suggested Answers

Dear students, the answers to the 2015 O level Science Physics 5076/ 5077 Paper 1 (MCQ) are shown below. All solutions/ answers are provided by teachers of Penciltutor School and the Singapore MOE or UCLES bears no responsibility for these suggested solutions/ answers. As usual, if you find any errors in our solutions or if you need an explanation, kindly send an email to admin@penciltutor.com.

Wednesday, November 11, 2015

2015 O level Pure Chemistry 5073 Paper 1 (MCQ) Suggested Answers

Dear students, the answers to the 2015 O level  Pure Chemistry 5073 Paper 1 (MCQ) are shown below. All solutions/ answers are provided by teachers of Penciltutor School and the Singapore MOE or UCLES bears no responsibility for these suggested solutions/ answers. As usual, if you find any errors in our solutions or if you need an explanation, kindly send an email to admin@penciltutor.com.


Friday, November 6, 2015

Suggested answers to 2015 O level Combined Humanities (Social Studies) 2204 Paper 1

Dear students, the answers to the 2015 O level Combined Humanities (Social Studies) 2204 Paper 1 have been uploaded at www.penciltutor.edu.sg. All solutions/ answers are provided by teachers of Penciltutor School and the Singapore MOE or UCLES bears no responsibility for these suggested solutions/ answers. As usual, if you find any errors in our solutions or if you need an explanation, kindly send an email to admin@penciltutor.com.

Suggested answers to 2015 O level Science Physics 5076/5077 Paper 2

Dear students, the answers to the 2015 O level Science Physics 5076/5077 Paper 2 have been uploaded at www.penciltutor.edu.sg. PLEASE BE INFORMED THAT WE WERE UNABLE TO GATHER ALL QUESTIONS FOR THIS PAPER FROM OUR STUDENTS AND THAT SOME QUESTIONS WERE ALSO NOT ACCURATELY REMEMBERED. All solutions/ answers are provided by teachers of Penciltutor School and the Singapore MOE or UCLES bears no responsibility for these suggested solutions/ answers. As usual, if you find any errors in our solutions or if you need an explanation, kindly send an email to admin@penciltutor.com.

Thursday, November 5, 2015

Explanation to 2015 O level Pure Physics 5059 Paper 1 (MCQ) Q26

In Q26, options A and D must be excluded as the refracted rays are diverging.

In both options B and C, the refracted ray bends towards the normal of the surface to the lens. For option B, according to the ray diagram, the image must form on the same side as the object.



Diverging lens always produces an image on the same side as the object. A converging lens produces an image on the same side as the object only when the object is placed in front of the focal point. However a ray that approaches a converging lens as shown in option B needs to be parallel to the principal axis or converge towards the principal focus.


Since the emergent ray from the lens is neither parallel to the principal axis nor converging to a point on the other side of the object, B cannot be a converging lens. Thus C is the converging lens where an image is formed on the other side. Option C shows the typical ray diagram for a two lens system. A common application of such a system can be found in hypermetropia (i.e longsightedness) lens correction.

 A closer look at the lens of the eye.




2015 O level Pure Physics 5059 Paper 1 (MCQ) Suggested Answers

Dear students, the answers to the 2015 O level  Pure Physics 5059 Paper 1 (MCQ) have been uploaded at www.penciltutor.edu.sg. All solutions/ answers are provided by teachers of Penciltutor School and the Singapore MOE or UCLES bears no responsibility for these suggested solutions/ answers. As usual, if you find any errors in our solutions or if you need an explanation, kindly send an email to admin@penciltutor.com.