71. When a glass rod is rubbed with silk, both glass rod and silk

1. 1. Acquire equal and similar charges

   
   
   

   2. Acquire equal and opposite charges

   
   
   

   3. Acquire unequal and opposite charges

   
   
   

   4. Acquire unequal and similar charges

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

---

72. A suitable unit for expressing electric field strength is

1. 1. V / C

   
   
   

   2. A - m

   
   
   

   3. C / m²

   
   
   

   4. N / C

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

---

---

73. A proton, when accelerated through a potential difference of V volts, has an associated wavelength, an a-particle must be accelerated through a potential difference of

1. 1. V volts

   
   
   

   2. 4 V volts

   
   
   

   3. 2 V volts

   
   
   

   4. V / 8 volts

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

---

74. Two charges of 1 C an 5 C are placed at some distance in air. The ratio of the forces acting on them is

1. 1. 1 : 25

   
   
   

   2. 1 : 5

   
   
   

   3. 1 : 1

   
   
   

   4. 5 : 1

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

---

---

75. For high frequency, the capacity offers

1. 1. More resistance

   
   
   

   2. Less resistance

   
   
   

   3. Zero resistance

   
   
   

   4. None of these

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

---