Neco Physics 2001 Past Questions and Answers

Question 26:

• NECO 2001

How much heat is required to convert 5.0g of ice at 0 ° C to water at the boiling point? (Specific latent heat of ice = 336Jg^-1 specific heat capacity of water = 4.2Jg^-1K^-1)

A. 420 J
B. 1680 J
C. 1701 J
D. 2100 J
E. 3780 J

Question 27:

• NECO 2001

What gives rise to the line spectra observed in atoms?

A. Change of an electron from a higher to a lower energy level in the atom
B. Disturbed protons in the nucleus
C. Excitation of an electron in the atom
D. Kinetic energy of a moving atom
E. Potential energy of an electron inside an atom

Question 28:

• NECO 2001

A lead-acid accumulator is used in preference to a dry battery in a car because ____________

A. A dry battery cannot supply the necessary high voltage
B. A dry battery would not operate on a cold frosty morning
C. The accumulator can give a bigger current and can be recharged
D. The accumulator can supply a.c
E. The chemicals used in a dry battery constitute a fire hazard.

Question 29:

• NECO 2001

A metal has a work function of 3.0 eV. What is the threshold frequency of the metal when electrons are just liberated from the metal.(1 eV = 1.6 × 10-19J; h = 6.6 × 10-34Js)

A. 4.8 × 10^-19Hz
B. 9.3 × 10^-7Hz
C. 4.8 × 10¹⁴Hz
D. 7.3 × 10¹⁴Hz
E. 9.3 × 10¹⁴Hz

Question 30:

• NECO 2001

A body whose initial velocity is u is uniformly accelerated to a final velocity v in t seconds. If the distance travelled is s, and the acceleration is a, which equation is INCORRECT for the motion of the body?

A. S = ut+\(\frac{1}{2}\)at²
B. V² = u² + 2as
C. V =u + at
D. V = u + 2as
E. S = \(\frac{1}{2}\)(u+v)t