NECO Physics Past Questions & Answers - Page 24

116.

If the distance between the plates of a parallel plate capacitor is decreased, its capacitance

A.

becomes zero

B.

decreases

C.

increases

D.

is halved

E.

remains the same

Correct answer is C

No explanation has been provided for this answer.

117.

A radioactive isotope has a half-life of 8 days. What fraction of the atoms will remain after 72 days?

A.

9.766 × 10-4

B.

1.736 ×10-3

C.

1.953 ×10-3

D.

3.472 × 10-3

E.

3.906 x 10-3

Correct answer is C

No explanation has been provided for this answer.

118.

Which of the following is used as a depolarizer in a Denial cell?

A.

Ammonium chloride

B.

Copper (II) tetra Oxo sulphate (VI) solution

C.

Manganese (IV) oxide

D.

Tetraoxosulphate (VI) acid

E.

Water

Correct answer is B

No explanation has been provided for this answer.

119.

Emission spectra are caused by

A.

kinetic energy of moving atoms

B.

potential energy of an electron in an atom

C.

transition of an electron from a higher energy level to a lower energy level

D.

transition of an electron from a lower energy level to higher energy level

E.

transition of excited protons in the nucleus

Correct answer is C

No explanation has been provided for this answer.

120.

A current flows in a series circuit containing a resistor, R, an inductor, L and a capacitor, C. Which of the following is true of the power dissipated in the circuit component(s)?

A.

The power dissipated in L is greater than zero

B.

The power dissipated in R is zero

C.

The sum of the power dissipated in L and C is equal to that in R

D.

The sum of the power dissipated in L and C is greater than in R

E.

The sum of the power dissipated in L and C is zero

Correct answer is E

No explanation has been provided for this answer.