Question 4601:

• NECO 2009

Which of the following pairs of musical instruments produce sound due to the vibration of air column?

A. Bell and piano
B. Guitar and flute
C. Trumpet and drum
D. Trumpet and flute
E. Violin and organ

Question 4602:

• NECO 2009

Calculate the heat energy lost when 10g of boiling water changes to ice at 0°C. [Specific latent heat of ice 336Jg^-1 . Specific heat capacity of water 4.2Jg^-1 K^-1]

A. 840J
B. 3360J
C. 3420J
D. 4200J
E. 7560J

Question 4603:

• NECO 2009

An effort P applied at one end of a crowbar just overcomes the resistance W at the lid of a tin. The mechanical advantage of the crowbar is expressed as ____________

A. W + P
B. P - W
C. \(\frac{w}{p}\)
D. \(\frac{p}{w}\)
E. Wp

Question 4604:

• NECO 2009

The phenomenon of photoelectric effect is used in the following EXCEPT

A. Automatic doors
B. Bugler alarm
C. Electric fire alarm
D. Sound production from film tracks
E. Television cameras

Question 4605:

• NECO 2009

Calculate the work done in charging a capacitor of capacitance 20µF through a potential difference of 1000V.

A. 0.02 J
B. 0.10 J
C. 0.20 J
D. 1.00 J
E. 10.00 J