PHYSICS PRACTICAL
GRADE XII
Practical Courses [32 Hours ]
The practical work that students do during their course is aimed at providing them learning opportunities to accomplish competency number 2 and 3 of the syllabus as well as reinforcing their learning of the theoretical subject content. This part of the syllabus focuses more on skill building than knowledge building. Students must be aware of the importance of precision, accuracy, significant figures, range and errors while collecting, processing, analyzing and communicating data. Likewise, graphical method of analysis and drawing conclusion should be encouraged wherever possible.
Students should
1. learn to use metre rule for measuring length, Vernier-calipers for measuring small thicknesses, internal and external diameters of cylindrical objects and depths of holes, spherometer for measuring radius of curvature of spherical surfaces and micrometer screw-gauge for measuring diameter of small spherical or cylindrical objects and very small thicknesses, traveling microscope with Vernier scale for measuring small distances, top-pan balance for measuring small masses, stop watch for measuring time interval, laboratory thermometer for measuring temperature, protractor for measuring angle), ammeter and milli-ammeter for measuring electric current and voltmeter for measuring electric potential difference.
2. learn to measure precisely up to the least count of the measuring instrument-
metre rule – 0.001m or 1 mm
Vernier calipers - 0.1 mm
Spherometer - 0.01 mm
micrometer screw gauge - 0.01 mm
stop watch - 0.01s
laboratory thermometer - 0.5°C
protractor - 1°
3. learn to repeat readings and take the average value
4. learn to draw a standard table, with appropriate heading and unit for every column for storing data
5. learn to plot a graph using standard format, draw suitable trend lines, determine gradient, intercepts and area and use them to draw appropriate conclusion
6. learn to estimate and handle uncertainties.
In each academic year, students should perform 10 experiments, either listed below or designed by teacher, so that no more than three experiments come from the same unit of this syllabus.
Practical Activities for Grade 12
I. Mechanics
1. Use of Simple pendulum for the determination of the value of ‘g’ in the laboratory by graphically analyzing the variation of period of oscillations with length of the pendulum.
2. Determination of the surface tension of water by capillary tube method by graphically analyzing the variation of by graphically analyzing the variation of height of the liquid against the diameter of capillary tube for five capillaries of different diameters dipped in water simultaneously.
3. Determination of the coefficient of viscosity of liquid by Stoke’s method by graphically analyzing the variation of time taken for six metal balls of different diameters to travel the same distance in the given liquid with respect to their diameters.
II. Wave and Optics
4. Determination of the wavelength of He-Ne laser light by passing a plane diffraction grating.
5. Determination of the frequency of A.C. Mains using sonometer and graphically analyzing the variation of the ratio of resonating lengths with respect to the frequency of tuning fork using tuning forks of different frequencies.
6. Determination of velocity of sound in air at NTP using resonance tube.
III. Electricity and magnetism
7. Use of potentiometer for the
a) Comparison of emf’s of two cells
b) Determination of the internal resistance of a cell
8. Study the variation or resistance of a thermistor with temperature.
9. Use of deflection magnetometer to determination of the pole strength and magnetic moment of a bar magnet
10. Determine the magnetic field strength of a bar magnet stuck on table by graphically analyzing the period of torsional motion of a freely suspended bar magnet and its distance from the near pole of the fixed magnet along its long axis.
IV. Modern Physics
11. Study the I-V characteristics of a semiconductor diode.
