ISC 2014 Physics Practical Question Paper for Class 12

About this paper

This is ISC Class 12 Physics Paper 2 (Practical), set by CISCE for the 2014 examination (paper code 861 B). It runs for three hours plus fifteen minutes of reading time, and candidates are told not to spend more than one and a half hours on Question 1. Question 1 (10 marks) finds the focal length of a convex lens by the no parallax method: six object distances between 20 cm and 70 cm, a table of u, v, p and q, and a graph of q against p whose slope gives f. Question 2 (7 marks) is an experiment based on the Wheatstone bridge principle using a metre-scale wire, a coiled wire, a resistance box and a galvanometer. This copy has only the first two of the paper's three printed pages, so the rest of Question 2 is not shown.

Exam

ISC Class 12

Subject

Physics Practical

Year

2014

Paper code

861 B

Time allowed

3 hours + 15 min reading

Pages

2

Answers included

No, questions only

Paper pattern

• Question 1

  10 marks

  Focal length of a convex lens by the no parallax method, with a graph of q against p

• Question 2

  7 marks

  Experiment based on the Wheatstone bridge principle (only the apparatus list is shown in this copy)

Topics covered

• Focal length of a convex lens
• No parallax method
• Graph plotting and slope of the line of best fit
• Wheatstone bridge principle

Questions from this paper

1. With the object pin at the 0 cm mark and the convex lens at the 70 cm mark (u = 70 cm), remove the tip-to-tip parallax between the image pin and the inverted image, and record the image distance v correct to one decimal place.
2. Repeat the experiment for five more values of u in the range 20 cm to 70 cm, and each time find v and calculate q = uv/100 and p = (u + v)/10.
3. Plot a graph of q against p with the origin at (0, 0), draw the line of best fit, find its slope m to three significant figures and calculate the focal length f = 10 × m.