Which among the following is a property of Insulator?

A. The electrons of the outer orbits are loosely bound to the nucleus , however can not flow through them
B. The electrons of the outer orbits are tightly bound to the nucleus and can not flow through them
C. The electrons of the outer orbits are loosely bound to the nucleus , and can flow through them
D. None of the above
✅ The correct answer is option B.

Which among the following is true about Total Internal Reflection?

A. A ray passing from rarer to denser medium and not able to pass to denser medium at an angle greater than critical angle
B. A ray passing from denser to rarer medium and not able to pass to rarer medium at an angle greater than critical angle
C. A ray passing from either denser to rarer medium or rarer to denser medium and not able to pass any medium at an angle smaller than critical angle
D. None of the above
✅ The correct answer is option B.

Which among the following is true regarding Sound Waves?

A. They are longitudinal waves and material medium is not required for their propagation
B. They are transverse waves and material medium is required for their propagation
C. They are longitudinal waves and material medium is required for their propagation
D. They are transverse waves and material medium is not required for their propagation
✅ The correct answer is option C.

Which among the following is true about conduction, convection and radiation mode of transfer of heat?

A. A Medium is required for conduction but not required for convection and radiation
B. A medium is required for conduction, convection and radiation
C. A medium is required for conduction and convection but not required for radiation
D. A medium is not required for conduction and convectio, radiation
✅ The correct answer is option C.