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Page 1 Delhi SET I Page 1 of 20 Final Draft 12/3/2013 2: 00 pm MARKING SCHEME SET 55/1/1 Q. No. Expected Answer / Value Points Marks Total Marks 1. Magnitude of the drift velocity of charge carrier per unit Electric field is called mobility. Alternatively, µ = E v d | | or m et SI unit = m 2 / (volt second) or ms -1 N -1 C ½ ½ 1 2. Modulation Index = c m a a = 1/2 = 0.5 ½ ½ 1 3. If Electric field is not normal, it will have non-zero component along the surface. In that case, work would be done in moving a charge on an equipotential surface. 1 1 4. Glass. In glass there is no effect of electromagnetic induction, due to presence of Earth’s magnetic field, unlike in the case of metallic ball. ½ ½ 1 5. 1 1 6. 20cm 1 1 7. Perpendicular to the plane formed by / [Note: Give full credit for writing the expression.] ½ ½ 1 8. X: Channel It connects the Transmitter to the Receiver ½ ½ 1 Page 2 Delhi SET I Page 1 of 20 Final Draft 12/3/2013 2: 00 pm MARKING SCHEME SET 55/1/1 Q. No. Expected Answer / Value Points Marks Total Marks 1. Magnitude of the drift velocity of charge carrier per unit Electric field is called mobility. Alternatively, µ = E v d | | or m et SI unit = m 2 / (volt second) or ms -1 N -1 C ½ ½ 1 2. Modulation Index = c m a a = 1/2 = 0.5 ½ ½ 1 3. If Electric field is not normal, it will have non-zero component along the surface. In that case, work would be done in moving a charge on an equipotential surface. 1 1 4. Glass. In glass there is no effect of electromagnetic induction, due to presence of Earth’s magnetic field, unlike in the case of metallic ball. ½ ½ 1 5. 1 1 6. 20cm 1 1 7. Perpendicular to the plane formed by / [Note: Give full credit for writing the expression.] ½ ½ 1 8. X: Channel It connects the Transmitter to the Receiver ½ ½ 1 Delhi SET I Page 2 of 20 Final Draft 12/3/2013 2: 00 pm 9. A: Paramagnetic B: Diamagnetic Susceptibility For A: positive For B: negative ½ ½ ½ ½ 2 10. cos = 5 10 10 cos0 ! 50 ! =5 10 10 cos60 ! = 25 N ! ½ ½ ½ ½ 2 11. In the first case, the overlapping of the contributions of the wavelets from two halves of a single slit produces a minimum because corresponding wavelets from two halves have a path difference of 2 ? . In the second case, the overlapping of the wavefronts from the two slits produces first maximum because these wavefronts have the path difference of #. (Alternatively, if a student writes the conditions given below, give full credit.) Condition for first minimum in single slit diffraction is , ˜ ? / a, Whereas in case of two narrow slits separated by distance a, first maximum occurs at angle ˜ ? / a [Note: Award 1 mark even if the candidate attempts this question partly.] 1 1 2 Identification of magnetic material ½ + ½ Susceptibility ½ + ½ Finding flux in two cases 1+1 Explanation of the given statement 1 + 1 Page 3 Delhi SET I Page 1 of 20 Final Draft 12/3/2013 2: 00 pm MARKING SCHEME SET 55/1/1 Q. No. Expected Answer / Value Points Marks Total Marks 1. Magnitude of the drift velocity of charge carrier per unit Electric field is called mobility. Alternatively, µ = E v d | | or m et SI unit = m 2 / (volt second) or ms -1 N -1 C ½ ½ 1 2. Modulation Index = c m a a = 1/2 = 0.5 ½ ½ 1 3. If Electric field is not normal, it will have non-zero component along the surface. In that case, work would be done in moving a charge on an equipotential surface. 1 1 4. Glass. In glass there is no effect of electromagnetic induction, due to presence of Earth’s magnetic field, unlike in the case of metallic ball. ½ ½ 1 5. 1 1 6. 20cm 1 1 7. Perpendicular to the plane formed by / [Note: Give full credit for writing the expression.] ½ ½ 1 8. X: Channel It connects the Transmitter to the Receiver ½ ½ 1 Delhi SET I Page 2 of 20 Final Draft 12/3/2013 2: 00 pm 9. A: Paramagnetic B: Diamagnetic Susceptibility For A: positive For B: negative ½ ½ ½ ½ 2 10. cos = 5 10 10 cos0 ! 50 ! =5 10 10 cos60 ! = 25 N ! ½ ½ ½ ½ 2 11. In the first case, the overlapping of the contributions of the wavelets from two halves of a single slit produces a minimum because corresponding wavelets from two halves have a path difference of 2 ? . In the second case, the overlapping of the wavefronts from the two slits produces first maximum because these wavefronts have the path difference of #. (Alternatively, if a student writes the conditions given below, give full credit.) Condition for first minimum in single slit diffraction is , ˜ ? / a, Whereas in case of two narrow slits separated by distance a, first maximum occurs at angle ˜ ? / a [Note: Award 1 mark even if the candidate attempts this question partly.] 1 1 2 Identification of magnetic material ½ + ½ Susceptibility ½ + ½ Finding flux in two cases 1+1 Explanation of the given statement 1 + 1 Delhi SET I Page 3 of 20 Final Draft 12/3/2013 2: 00 pm 12. Truth Table Input Output A B Y’ Y 0 0 0 0 0 1 1 0 1 0 1 1 1 1 1 1 Gate R: OR Gate S: AND Gate OR P: NAND Gate Q: OR Gate Truth Table Input Output A B X 0 0 1 1 0 1 0 1 1 1 1 1 1 ½ ½ ½ ½ 1 2 2 13. Junction rule: At any junction, the sum of the currents entering the junction is equal to the sum of currents leaving the junction. Alternatively, ? i =0 ½ Statements of two Laws ½ + ½ Justification ½ + ½ Truth Table 1 Names of gates used ½ + ½ Identification 1 Truth Table 1 Page 4 Delhi SET I Page 1 of 20 Final Draft 12/3/2013 2: 00 pm MARKING SCHEME SET 55/1/1 Q. No. Expected Answer / Value Points Marks Total Marks 1. Magnitude of the drift velocity of charge carrier per unit Electric field is called mobility. Alternatively, µ = E v d | | or m et SI unit = m 2 / (volt second) or ms -1 N -1 C ½ ½ 1 2. Modulation Index = c m a a = 1/2 = 0.5 ½ ½ 1 3. If Electric field is not normal, it will have non-zero component along the surface. In that case, work would be done in moving a charge on an equipotential surface. 1 1 4. Glass. In glass there is no effect of electromagnetic induction, due to presence of Earth’s magnetic field, unlike in the case of metallic ball. ½ ½ 1 5. 1 1 6. 20cm 1 1 7. Perpendicular to the plane formed by / [Note: Give full credit for writing the expression.] ½ ½ 1 8. X: Channel It connects the Transmitter to the Receiver ½ ½ 1 Delhi SET I Page 2 of 20 Final Draft 12/3/2013 2: 00 pm 9. A: Paramagnetic B: Diamagnetic Susceptibility For A: positive For B: negative ½ ½ ½ ½ 2 10. cos = 5 10 10 cos0 ! 50 ! =5 10 10 cos60 ! = 25 N ! ½ ½ ½ ½ 2 11. In the first case, the overlapping of the contributions of the wavelets from two halves of a single slit produces a minimum because corresponding wavelets from two halves have a path difference of 2 ? . In the second case, the overlapping of the wavefronts from the two slits produces first maximum because these wavefronts have the path difference of #. (Alternatively, if a student writes the conditions given below, give full credit.) Condition for first minimum in single slit diffraction is , ˜ ? / a, Whereas in case of two narrow slits separated by distance a, first maximum occurs at angle ˜ ? / a [Note: Award 1 mark even if the candidate attempts this question partly.] 1 1 2 Identification of magnetic material ½ + ½ Susceptibility ½ + ½ Finding flux in two cases 1+1 Explanation of the given statement 1 + 1 Delhi SET I Page 3 of 20 Final Draft 12/3/2013 2: 00 pm 12. Truth Table Input Output A B Y’ Y 0 0 0 0 0 1 1 0 1 0 1 1 1 1 1 1 Gate R: OR Gate S: AND Gate OR P: NAND Gate Q: OR Gate Truth Table Input Output A B X 0 0 1 1 0 1 0 1 1 1 1 1 1 ½ ½ ½ ½ 1 2 2 13. Junction rule: At any junction, the sum of the currents entering the junction is equal to the sum of currents leaving the junction. Alternatively, ? i =0 ½ Statements of two Laws ½ + ½ Justification ½ + ½ Truth Table 1 Names of gates used ½ + ½ Identification 1 Truth Table 1 Delhi SET I Page 4 of 20 Final Draft 12/3/2013 2: 00 pm Justification : Conservation of charge Loop rule: The Algebraic sum of changes in the potential around any closed loop involving resistors and cells in the loop is zero. Alternatively, ? ? V =0 , where ? V is the changes in potential Justification : Conservation of energy ½ ½ ½ 2 14. (i) Reactance of the capacitor will decrease, resulting in increase of the current in the circuit. Therefore the bulb will glow brighter. (ii) Increased resistance will decrease the current in the circuit, which will decrease glow of the bulb. [Note : Do not deduct any mark for not giving the reasons.] 1 1 2 15. It makes use of the principle that the energy of the charged particles / ions can be made to increase in presence of crossed Electric and magnetic fields. A normal Magnetic field acts on the charged particle and makes them move in a circular path .While moving from one dee to another; particle is acted upon by the alternating electric field, and is accelerated by this field, which increases the energy of the particle. 1 1 2 16. tpEsin? 4v3 = pEsin60 0 v ? pE = 8 Potential energy ½ ½ ½ Calculation of Potential energy of the dipole 2 Underlying principle 1 Brief working 1 Effect on glow of bulb in Part (i) 1 Part (ii) 1 Page 5 Delhi SET I Page 1 of 20 Final Draft 12/3/2013 2: 00 pm MARKING SCHEME SET 55/1/1 Q. No. Expected Answer / Value Points Marks Total Marks 1. Magnitude of the drift velocity of charge carrier per unit Electric field is called mobility. Alternatively, µ = E v d | | or m et SI unit = m 2 / (volt second) or ms -1 N -1 C ½ ½ 1 2. Modulation Index = c m a a = 1/2 = 0.5 ½ ½ 1 3. If Electric field is not normal, it will have non-zero component along the surface. In that case, work would be done in moving a charge on an equipotential surface. 1 1 4. Glass. In glass there is no effect of electromagnetic induction, due to presence of Earth’s magnetic field, unlike in the case of metallic ball. ½ ½ 1 5. 1 1 6. 20cm 1 1 7. Perpendicular to the plane formed by / [Note: Give full credit for writing the expression.] ½ ½ 1 8. X: Channel It connects the Transmitter to the Receiver ½ ½ 1 Delhi SET I Page 2 of 20 Final Draft 12/3/2013 2: 00 pm 9. A: Paramagnetic B: Diamagnetic Susceptibility For A: positive For B: negative ½ ½ ½ ½ 2 10. cos = 5 10 10 cos0 ! 50 ! =5 10 10 cos60 ! = 25 N ! ½ ½ ½ ½ 2 11. In the first case, the overlapping of the contributions of the wavelets from two halves of a single slit produces a minimum because corresponding wavelets from two halves have a path difference of 2 ? . In the second case, the overlapping of the wavefronts from the two slits produces first maximum because these wavefronts have the path difference of #. (Alternatively, if a student writes the conditions given below, give full credit.) Condition for first minimum in single slit diffraction is , ˜ ? / a, Whereas in case of two narrow slits separated by distance a, first maximum occurs at angle ˜ ? / a [Note: Award 1 mark even if the candidate attempts this question partly.] 1 1 2 Identification of magnetic material ½ + ½ Susceptibility ½ + ½ Finding flux in two cases 1+1 Explanation of the given statement 1 + 1 Delhi SET I Page 3 of 20 Final Draft 12/3/2013 2: 00 pm 12. Truth Table Input Output A B Y’ Y 0 0 0 0 0 1 1 0 1 0 1 1 1 1 1 1 Gate R: OR Gate S: AND Gate OR P: NAND Gate Q: OR Gate Truth Table Input Output A B X 0 0 1 1 0 1 0 1 1 1 1 1 1 ½ ½ ½ ½ 1 2 2 13. Junction rule: At any junction, the sum of the currents entering the junction is equal to the sum of currents leaving the junction. Alternatively, ? i =0 ½ Statements of two Laws ½ + ½ Justification ½ + ½ Truth Table 1 Names of gates used ½ + ½ Identification 1 Truth Table 1 Delhi SET I Page 4 of 20 Final Draft 12/3/2013 2: 00 pm Justification : Conservation of charge Loop rule: The Algebraic sum of changes in the potential around any closed loop involving resistors and cells in the loop is zero. Alternatively, ? ? V =0 , where ? V is the changes in potential Justification : Conservation of energy ½ ½ ½ 2 14. (i) Reactance of the capacitor will decrease, resulting in increase of the current in the circuit. Therefore the bulb will glow brighter. (ii) Increased resistance will decrease the current in the circuit, which will decrease glow of the bulb. [Note : Do not deduct any mark for not giving the reasons.] 1 1 2 15. It makes use of the principle that the energy of the charged particles / ions can be made to increase in presence of crossed Electric and magnetic fields. A normal Magnetic field acts on the charged particle and makes them move in a circular path .While moving from one dee to another; particle is acted upon by the alternating electric field, and is accelerated by this field, which increases the energy of the particle. 1 1 2 16. tpEsin? 4v3 = pEsin60 0 v ? pE = 8 Potential energy ½ ½ ½ Calculation of Potential energy of the dipole 2 Underlying principle 1 Brief working 1 Effect on glow of bulb in Part (i) 1 Part (ii) 1 Delhi SET I Page 5 of 20 Final Draft 12/3/2013 2: 00 pm U = -pE cos = -8 x cos 60 0 = -4J [Give full credit to alternative methods of finding Potential energy.] ½ 2 17. (a) de Broglie wavelength is given by ?= 2 3456 As mass of proton < mass of deuteron and q p = q d and v is same => ?p > ? d for same accelerating potential. (b) Momentum = 2 7 ? ? p > ? d ? momentum of proton will be less , than that of deuteron ½ ½ ½ ½ 2 18. (a) Power = h, where n = no. of photons per second 2.0 x 10 -3 = × 6.6 × 10 < × 6 × 10 < n = . = >? @.@ × >?A ×@× BA = 0.050 x 10 17 = 5x 10 15 photons / second [Note: Even if the student doesn’t write the formula but calculates correctly, give full credit to this part] (b) ½ ½ Part (a) and reason ½ + ½ Part (b) and reason ½ + ½ (a) Estimation of no. of photons per second 1 (b) Plot showing the variation 1Read More
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