Effective mass of an electron in an semiconductor
The correct answer is: can never be negative
Two identical, insulated sphere have different charges. Sphere 1 has –9.6 × 10–18 C. Sphere 2 has 60 excess electron. If the two sphere are brought into contact and then separated. What charge will each have?
A charge +q is placed (a, 0, 0) and another +q is placed (-a, 0, 0). A charge –q is placed at the origin. If it is slightly displaced along y-axis. Then
The correct answer is: It will execute SHM
Which of the following is a possible value of charge?
The correct answer is: 12.8 × 10–19 C
Which of the following statement concerning lightning is/are correct?
1. It is a result of charging
2. The charge at the bottom of the clouds and those induced on the top of the roofs of buildings form a very strong electric field.
3. Lightning cause the thunder we hear
A negative charged rod is held near a conductor X that is earthed shown in the figure. Here X is
The correct answer is: Positively charged and at earth potential
Which of the following should not be done during lightning.
1. Stay in a building with a lightning conductor installed on the roof.
2. Stand near a window with a metal frame.
3. Crouch down in an open field.
1 and 3 are the preventive measures to stay safe from lightning
The diagram shows five charged metal spheres suspended by string. The charge of each sphere is +5C, –2C, +3C, –4C and +2C as shown. If the five spheres simultaneously contact together. Find the net charge on them.
The correct answer is: +4C
Two spheres P and Q are supported on two insulated stands and placed next to each other. Sphere P has a charge of +10C and sphere Q is neutral which of the following statement is correct?
The correct answer is: After some time, Q is still neutral
A charged of Q coulomb is placed on a solid piece of metal of irregular shape the charge will distribute itself.
The correct answer is: Such that the potential energy of the system is minimised