physics

The theory of electronic conduction in solids; which satisfactorily explains the properties of conductors, insulators and semi-conductor is?

A. string theory B. particle theory C. group theory D. band theory Correct Answer: Option D - band theory

4 years ago

A radioactive element has a half life of 4 days. The fraction that has decayed in 16 days is?

A. (15)/16 B. (1)/16 C. (3)/4 D. (1)/4 Correct Answer: Option A = (15)/16 Explanation 16 days = 4 half…

4 years ago

One of the properties of gamma rays is that they are?

A. neutral B. massive C. positively charged D. negatively charged Correct Answer: Option A - neutral

4 years ago

The battery connection that permits current to flow across a p-n junction is called?

A. reverse biased B. forward biased C. amplification. D. rectification Correct Answer: Option B - forward biased

4 years ago

The process through which free electrons leave the surface of hot metal is known as?

A. photon emission B. photo emission C. thermionic emission D. electron emission Correct Answer: Option C = thermionic emission

4 years ago

Which of statements below about machines are true?

I. Work done by load is always less than the work done by effort. II. All machines are made of…

4 years ago

The correct unit of energy density is?

A. kg m3 s-2 B. kg m2 s-2 C. kg m-3 s-2 D. kg m-1 s-2 Correct Answer: Option D = kg m-1 s-2

4 years ago

The component of vector X along the direction of vector Y is zero when?

A. X and Y are in opposite directions to each other B. X is at an angle of 45° to…

4 years ago

If the radius of the earth is 6.4 x 106m; the escape velocity of a satellite from the earth is? [g = 10 ms−²]

A. 1.13 x 104 ms-1 B. 9.00 x 103 ms-1 C. 8.00 x 103 ms-1 D. 1.27 x 104 ms-1 Correct Answer: Option A…

4 years ago