CBSE Class 12 Physics Demonstration Data

More data, this time, for the Class XII Physics Demonstrations…

Tangent Law Demonstration

Number of turns used = 2
Internal diameter of coil = 0.14 m
External diameter of coil = 0.1414 m

Least count of ammeter = 0.25 A

Zero error of ammeter = 0 A

S. No.

Number of turns (n)

Current (I)

Deflection (θ)

tan θ

1

2

0.75

22.5

0.4142

2

2

1.5

40

0.8391

3

2

1.75

45

1

4

2

2

50

1.91

Calculations:
Mean diameter of coil = 0.14 m
Mean radius of coil = 0.07 m
Value of horizontal component of Earth’s magnetic field:

  1. H1 = 3.24 x 10^-5 tesla
  2. H2 = 3.2 x 10^-5 tesla
  3. H3 = 3.14 x 10^-5 tesla

Mean value of H = 3.19 x 10^-5 tesla

Result:
Experimental value of H = 3.19 x 10^-5 tesla
Actual value of H = 3.2 x 10^-5 tesla
Difference = 0.01 x 10^-5 tesla
% error = 3.125%

Refractive Index Demonstration

Rough focal length of convex lens = 10 cm

Arrangement

Height of tip of optical needle

Focal length

(x cm)

from lens surface x1 cm

from plane mirror x2 cm

Mean x cm

Convex lens on plane mirror

9.8

10.2

10

fg = 10

Convex lens on plane mirror with water in between

14.8

15.2

15

F = 15

Convex lens on plane mirror with glycerol in between

20.8

21.2

21

F = 21

Calculations:

  1. R = f = 10 cm
  2. fwater = -30 cm
  3. fglycerol = -19 cm
  4. Refractive index of water = 1.33
  5. Refractive index of glycerol = 1.53

15 replies on “CBSE Class 12 Physics Demonstration Data”

Oh thank you so much! Went mad looking for correct readings…am eternally grateful to you…btw, could you get two more readings for the tangent galvanometer? We were asked to record 6…

@Bhavika: No problem. :) I knew loads of people would be needing this data…I thought I could help them out. Anyway, getting two more reading might be problem, because I’d be going to school now only on the day of the practicals…I don’t think it’ll matter really, because our teacher (physics HoD) said four readings were enough.

hey ankur
thanx a ton 4 d readings
i don’t think u know me
bhavika told me bout the readings
but still a big thank you

wow
thanks for the readings!
during our prac dunno wtf was wrong wid the apparatus,couldnt get 1 good reading for the tang galv.
thanks again!

thanx….
thanx a lot…………..
i was going mad thinking how to write the demonstrations…
thanx 4 d help n cordination. u made it so easier 4 me 2 complete my experiments now….

Thanks a lot Sirji!!!!i myself am frm DPS Vk…got my prac next week n abhi tak file ka koi ata pata nahi hai…I owe u truly

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