Form 4 Physics Questions and Answers on Thin Lenses

In this session, we are going to solve Form 4 Physics questions on thin lenses. Answers are in video format.

Lessons (18)     SHARE

• 1.    An object placed in front of a convex lens of focal length 10cm produces an image at a distance of 15cm from the lens and on the same side as the object. Determine the position of the object.
  2m 57s

• 2.    (a) Draw a ray diagram to show how a convex lens works as a magnifying glass. (b) The diagram in figure 3 shows a certain eye defect. (i) Name the defect. (ii) Draw on the same diagram an arrangement to correct the defect.
  7m 52s

• 3.    Fig. 8 shows an object O placed in front of a concave lens with principal foci F and F’. Construct a ray diagram to locate the position of the image.
  3m 55s

• 4.    Fig. 2 drawn to scale, shows a lens L1 placed 30cm from an object O. The image is formed on the screen S 50cm from the lens. On the figure, draw appropriate rays then determine the focal length of the lens.
  3m 24s

• 5.    Sketch a diagram to show the position of an object, when a converging lens is used as a magnifying glass.
  6m 20s

• 6.    Figure 21 shows a converging lens whose focal point F is marked. An object is placed in front of the lens such that a real magnified image is formed by the lens. Sketch on the same diagram, a ray diagram to represent this.
  4m 8s

• 7.    Figure 13 represents an object O placed 10cm in front of a diverging lens. F is the focal point of the lens. Draw rays to locate the position of the image. Determine the image distance.
  4m 10s

• 8.    Figure 10 (drawn to scale) shows an image L formed by a diverging lens, L. On the same diagram, draw appropriate rays to locate the position of object. Determine the object distance.
  4m 22s

• 9.    (a) Figure 8 shows an experimental set-up consisting of a mounted lens L, a screen S, a meter rule and a candle. (i) Describe how the set-up may be used to determine the focal length, f, of the lens. (ii) State the reason why the set-up would not work if the lens were replaced with a diverging lens (b) The graph in figure 9 shows the relationship between #1/u# and #1/v# for a converging lens where
  8m 53s

• 10.    A vertical object is placed at the focal point F of a diverging lens as shown in figure 16. Sketch a ray diagram to show the image of the object.
  3m 13s

• 11.    An illustrated vertical object is initially placed on the principal axis of a converging lens and 32cm from it. The focal length of the lens is 15cm. The object is now placed at a point 12cm from the lens and on the same side. State two changes other than magnification that are observed on the image formed due to this change.
  3m 27s

• 12.    A vertical object is placed 20cm in front of a convex lens of focal length 5cm. (i) Determine: (I) The image Distance (II) The magnification. (ii) State two characteristics of the image.
  3m 33s

• 13.    State what it is meant by the term accommodation as applied to the human eye
  0m 57s

• 14.    (a) Figures 11 (a) and (b) show diagrams of the human eye. (i) Sketch in figure 11 (a) a ray diagram to show short sightedness. (ii) Sketch in figure 11 (b) a ray diagram to show how lens can be used to correct the short sightedness. (b) Figure 12 shows the features of a simple camera. (i) Name the parts labeled A and B. (ii) A still object is placed at a certain distance from the camera. Explain
  11m 51s

• 15.    The diagram in figure 2 shows an object O laced in front of a converging lens. F and F’ are the principal foci for the lens. The object is now moved along the principal axis until a virtual image is produced. On the same diagram: (i) Draw the object O in the new position along the principal axis. (ii) Sketch rays to show formation of the virtual image.
  5m 17s

• 16.    Figure 7 shows how rays from a distant and a near object are focused inside a human eye with a certain defect. Name the defect and state the cause of this defect.
  1m 59s

• 17.    In an experiment, a pin, a converging lens and a plane mirror are arranged as shown in figure 4. The distance between the pin and the plane mirror is L cm while the distance between the lens and the plane mirror is q cm. The position of the pin is adjusted until its tip coincides with its real image. State the focal length of the lens.
  2m 32s

• 18.    (a) State the meaning of the term “principal focus” as applied in lenses. (b) You are provided with the following apparatus to determine the focal length of a lens; A biconvex lens and lens holder, a lit candle, a white screen, a meter rule. (i) Draw a diagram to show how you would arrange the above apparatus to determine the focal length of the lens (ii) Describe the procedure you would follow.
  7m 19s

---

Related Content

---

•  Form 4 chemistry questions and answers on metals
  

  Form 4 chemistry topical questions and answers on metals. Questions are available in video format.

  26 Video Lessons

•  Form 4 Mathematics Linear Programming Questions and Answers
  

  In this session, we are going to solve several questions on linear programming, a from 4 mathematics topic. Solutions are available in video format. All questions are exam standard and suitable for those preparing for KCSE exams.

  16 Video Lessons

•  Form 4 History and Government Lessons on International Relations
  

  In this session, we are going to learn about international relations, which is a form 4 history and government topic. Lessons are in video format. The lesson pdfs are also available for download.

  37 Video Lessons

•  Form 4 History and Government Lessons on World Wars
  

  In this online learning session, we are going to learn about world wars, which is a form 4 history and government topic.

  31 Video Lessons

•  Form 4 Maths area and approximation: Mid-Ordinate Rule questions and answers
  

  In this online learning session, we are going to solve Form 4 Mathematics questions are and approximation using mid-ordinate rule.

  9 Video Lessons

•  Form 4 Mathematics area and approximation: Integration questions and answers
  

  Form 4 Mathematics area and approximation: Integration questions and answers

  10 Video Lessons

•  Form 4 Mathematics Trigonometry III Online Lessons
  

  In this session, we are going to learn about trigonometry III, which is a form 4 mathematics topic.

  7 Video Lessons

•  Form 4 Chemistry Online Lessons on Extraction of Iron
  

  Form 4 Chemistry Online Lessons on Extraction of Iron. All lessons are in video format and pdf.

  4 Video Lessons

•  Form 4 Physics Floating and Sinking Questions and Answers
  

  In this session, we are going to solve floating and sinking questions for Physics Form 4.

  24 Video Lessons

•  Form 4 Mathematics area and approximation:Trapezoidal rule questions and answers
  

  In this online session, we are going to answer Form 4 Mathematics area and approximation:Trapezoidal rule questions. Answers are in video format.

  10 Video Lessons

•  Area and Approximation: Counting squares techniques questions and answers
  

  Form 4 Mathematics Area and Approximation: Counting squares techniques questions and answers

  2 Video Lessons

•  Form 4 Biology: Evolution Lessons
  

  Form 4 Biology Evolution Lessons. In this session, we are going to learn about evolution. Evolution is a form 4 Biology topic.

  6 Video Lessons

•  Form 4 Physics X-Rays Questions and Answers
  

  In this session, we are going to solve form 4 Physics X-Rays questions. Answers are available in video format. The questions are suitable for those preparing for KCSE exams.

  16 Video Lessons

•  Form 4 Biology Genetics Questions and Answers
  

  In this session, we are going to solve several Form 4 Biology questions on genetics. All questions are exam quality and very suitable for those preparing for KCSE exam.

  33 Video Lessons

•  Kiswahili Fasihi Simulizi Lessons and Notes
  

  Kiswahili Fasihi Simulizi Lessons and Notes. In this session, we are going to learn about fasihi simulizi. Lessons are available in video format. For each lesson, notes in pdf version are also available.

  162 Video Lessons

•  Form 4 Mathematics : Longitudes and Latitudes Topical Questions and Answers
  

  Form 4 Mathematics : Longitudes and Latitudes Topical Questions and Answers. In this session, we are going to solve several questions on longitudes and latitudes. Answers are available in video format. The questions are very useful to those preparing for KCSE examination.

  25 Video Lessons

•  Form 4 Chemistry: Radioactivity Questions and Answers
  

  Form 4 Chemistry Radioactivity Questions and Answers. We are going to answer questions on radioactivity. Students preparing for KCSE exams will find these questions very useful.

  26 Video Lessons

•  Form 4 Energy Changes in Chemical and Physical Processes Questions and Answers
  

  Form 4 Energy Changes in Chemical and Physical Processes Questions and Answers. In this session, we are going to solve several exam standard questions. Answers are available in video format.

  39 Video Lessons

•  Form 4 Electrochemistry Topical Questions and Answers
  

  In this session, several Form 4 Electrochemistry Questions will be solved. Answers will be given in video format.

  52 Video Lessons

•  Form 4 Acids, Bases and Salts Topical Questions and Answers
  

  In this session, several questions on acids, bases and salts will be solved. All answers are well explained and in video format. Very ideal for those preparing for KCSE exams.

  66 Video Lessons

•  Form 4 Matrices and Transformations Questions and Answers
  

  Matrices and Transformations Questions and Video Answers. Several questions have been answered. All answers are in video format.

  20 Video Lessons

•  Form 4 Chemistry Organic Chemistry II Questions and Answers
  

  Form 4 Chemistry Organic Chemistry II Topical Questions and Answers

  57 Video Lessons

•  Form 4 Physics Electromagnetic Spectrum Topical Questions and Answers
  

  Form 4 Physics Electromagnetic Spectrum Topical Questions and Answers. In this session, we are going to solve several revision question. All questions have video answers.

  15 Video Lessons

•  Integration and Its Applications Questions and Answers - Form 4 Calculus
  

  Integration and Its Applications Topical Questions and Answers - Form 4 Calculus In this course, we are going to learn through several revision questions on integration and its applications.

  21 Video Lessons

•  Form 4 Mathematics Statistics II Questions and Answers
  

  Form 4 Mathematics Statistics II Questions and Answers. Learn through well answered, high quality mathematics questions on Statistics II. Answers are available in video format.

  19 Video Lessons

•  Blossoms of the Savannah Essay Questions and Answers
  

  Blossoms of the Savannah Essay Questions and Answers. In this session, several questions on Blossoms of the Savannah will be answers.

  17 Video Lessons

•  Form 4 Oral Literature Revision Questions
  

  Form 4 Oral Literature Revision Questions. In this course, several oral literature revision questions will be tackled.

  14 Video Lessons

•  Form 4 Physics Uniform Circular Motion Questions and Answers
  

  Form 4 Physics Uniform Circular Motion Questions and Answers. Browse though questions and video solution for the Form 4 Physics topic on uniform circular motion. The answers are detailed and well explained.

  20 Video Lessons

•  Differentiation and Its Applications Questions and Answers
  

  This course contains many exam standard worked out questions on differentiation and its applications. All the questions have well elaborated video answers with explanations. Most of the questions have been derived from the past KCSE exams. More questions are being added continuously.

  20 Video Lessons

•  Form 4 Mathematics Lessons on Statistics 2
  

  In this course, we will discuss the following lessons: i) Assumed/working mean. ii) Median, quartiles, deciles and percentiles. iii) Ogive/cumulative frequency curve. iv)Variance and standard deviation.

  5 Video Lessons

•  Form 4 Matrices and Transformations Lessons
  

  The following areas will be covered in this course: (i) Finding the matrix of transformation given the object and image positions. (ii) Describing the nature of reflection, given the matrix of the reflection. (iii) Describe a given rotation using the matrix of transformation given. (iv)...

  7 Video Lessons