Question 4411:

• NECO 2001

The falling of light energy on a metal such that electrons are liberated from the metal is called ____________

A. Electron effect
B. Metal electron effect
C. Metal emission
D. Photoelectric effect
E. Photoemission

Question 4412:

• NECO 2001

A transformer is connected to a 250 V a.c. supply. The primary coil has 5000 turns and the secondary voltage is found to be 10 V. What is the number of turns in the secondary coil?

A. 100
B. 150
C. 200
D. 250
E. 300

Question 4413:

• NECO 2002

A negatively charged rod is brought near the cap of an electroscope. The cap is earthed momentarily while the charge is near to it. The rod is then removed. Which statement is correct?

A. The cap will be positively charged and the will be negatively charged
B. The cap will be negatively charged and the leaf will be positively changed
C. The cap and the leaf will be positively charged
D. The cap and the leaf will be negatively charged
E. None

Question 4414:

• NECO 2002

If the refractive index of water is 1.33, what is the critical angle for a water-air boundary?

A. 36.0 °
B. 40.2 °
C. 41.8 °
D. 48.8 °
E. 62.7 °

Question 4415:

• NECO 2002

What does NOT affect the rate of evaporation of a liquid ____________

A. Exposed surface area of the liquid
B. Humidity of the surroundings
C. Nature of the liquid
D. Temperature the liquid
E. Volume of the liquid.