Magnifying glasses are useful, because they create an enlarged

Q-1: Magnifying glasses are useful, because they create an enlarged:

1) virtual image behind the actual object.
2) real image behind the actual object.
3) virtual image in front of the actual object.
4) real image in front of the actual object.
ANSWER: 1 -- VIRTUAL IMAGE BEHIND THE ACTUAL OBJECT.

Q-2:  Which pot of water will boil LAST when all are heated by the same source?

1) aluminum pot
2) iron pot
3) brass pot
4) titanium pot
ANSWER: 4 -- TITANIUM POT

Q-3: How many atoms per unit cell are in a face-centered-cubic crystal?

1) two
2) four
3) six
4) eight
ANSWER: 2 -- FOUR

Q-4: Refractory metals are known for which of the following properties:

1) lack of chemical reactivity
2) low density
3) high melting point
4) high thermal conductivity
ANSWER: 3 -- HIGH MELTING POINT

Q-5: A small hole in a sheet of aluminum foil is used to diffract yellow light both under water and in a vacuum. Which is true?

1) light diffracts less in the water because its wavelength is larger.
2) light diffracts less in the water because its wavelength is smaller.
3) light diffracts more in the water because its wavelength is larger.
4) light diffracts more in the water because its wavelength is smaller.
ANSWER: 2 -- LIGHT DIFFRACTS LESS IN THE WATER BECAUSE ITS WAVELENGTH IS SMALLER

Q-6:  A 20 ohm resistor and a 60 ohm resistor are connected in parallel to a voltage source. If the current in the 60 ohm resistor is one ampere, the current in the 20 ohm resistor will be:

1) 1/3 ampere
2) 2/3 ampere
3) 1 ampere
4) 3 amperes
ANSWER: 4 -- 3 AMPERES

Q-7:  An LED is operated on a 12 volt automobile circuit. The voltage drop across the LED is 2 volts and the current must be limited to 50 milliamps to prevent its overheating and destruction. What size resistor must be used?

1) 60 ohms
2) 100 ohms
3) 120 ohms
4) 200 ohms
ANSWER: 4 -- 200 OHMS

Q-8:  Which is NOT a characteristic of a series circuit?

1) The current is the same throughout.
2) The total resistance is the sum of the individual resistance.
3) The voltage of the source equals the sum of the circuit's individual voltage drops.
4) The total resistance is the sum of the reciprocals of the individual resistances.
ANSWER: 4 -- THE TOTAL RESISTANCE IS THE SUM OF THE RECIPROCALS
OF THE RECIPROCAL OF THE INDIVIDUAL RESISTANCES.