ISC 2019 Physics Practical Question Paper for Class 12

About this paper

This is ISC Class 12 Physics Paper 2 (Practical), set by CISCE for the 2019 examination (paper code 861B). It carries 30 marks and runs for three hours plus fifteen minutes of reading time, with no more than one and a half hours to be spent on each experiment. Question 1 finds the focal length of a convex lens by the no parallax method for object distances from 70 cm down to 30 cm, plotting a graph whose slope S gives f = S × 10. Question 2 finds the resistance per unit length of a uniform wire using an ammeter, a voltmeter and a resistance box set from 1 Ω to 5 Ω, with the jockey fixed 75 cm along the wire. Question 3 is the assessment of the project and practical file by the Visiting Examiner.

Exam

ISC Class 12

Subject

Physics Practical

Year

2019

Paper code

861B

Maximum marks

30

Time allowed

3 hours + 15 min reading

Questions

3

Pages

4

Answers included

No, questions only

Paper pattern

• Question 1

  9 marks

  Focal length of a convex lens by the no parallax method, with a graph of y against x

• Question 2

  6 marks

  Resistance per unit length of a wire using an ammeter, voltmeter and resistance box

• Question 3

  15 marks

  Project (10 marks) and Physics practical file (5 marks) shown to the Visiting Examiner

Topics covered

• Focal length of a convex lens
• No parallax method
• Resistance per unit length of a wire
• Ohm's law with ammeter and voltmeter
• Graph plotting and slope of the line of best fit
• Project and practical file

Questions from this paper

1. With the object pin at the 0.0 cm mark and the lens at the 70.0 cm mark (u = 70.0 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 u = 60.0 cm, 50.0 cm, 40.0 cm and 30.0 cm, removing the parallax each time and finding v.
3. Plot a graph of y against x, draw a thin, uniform best fit line, find its slope S to three significant figures and calculate f = S × 10 with its unit.
4. With R = 1 Ω and the jockey at C so that AC = 75 cm, record the ammeter and voltmeter readings, then repeat for R = 2 Ω, 3 Ω, 4 Ω and 5 Ω.
5. Find r for each set to three significant figures, take the mean r₀ of the five values, and use it to calculate K, the resistance per unit length of the wire.