In the arrangement illustrated above, Y and B are yellow and blue transparent light filters respectively through the filters is

• A. blue
• B. red
• C. yellow
• D. Black

State three differences between geostationary satellites and polar satellites.

Convex mirror are used as driving mirrors because images formed are?

• A) erect, virtual and diminished
• B) erect, real and diminished
• C) erect, virtual and magnified
• D) inverted virtual and diminished

A radioactive material has a half-life of 1.0 hour If 200.0 g of it was present at 6 a.m. on a certain day, how many grams will have decayed by 9 a.m. on the same day?

• A. 175.0 g
• B. 150.0 g
• C. 100.0 g
• D. 187.5 g

A cube made of metal of linear expansivity \(\alpha\) is heated through a temperature \(\theta\). If the initial volume of the cube is V_o, the correct expression for the increase in volume of the cube is

• A. \(\frac{1}{3} \alpha V_o \theta\)
• B. \(\frac{1}{2} \alpha V_o \theta\)
• C. \(2 \alpha V_o \theta\)
• D. \(3 \alpha V_o \theta\)

Five 80-W and three 100W are run for 8 hours. If the cost of energy is N5.00 per unit, calculate the cost of running the lamp. [1 unit = 1 kWh]

• A. N280.00
• B. N28.00
• C. N7.20
• D. N1.44

Which of the following waves are longitudinal waves? l. Ripples on the surface of water II. Waves produced by a tuning fork vibrating in air III. Light waves IV. Waves produced by a flute

• A. I and II only
• B. I and III only
• C. II and III only
• D. II and IV only

The circuit below illustrates a standard resistor R, voltage source E and a lamp L connected in series. If the temperature of R is increased, the brightness of the lamp will

• A. increase sharply
• B. decrease slightly
• C. remains the same
• D. increase gradually

An a.c. generator can be converted to a d.c. electric motor by replacing the

• A. slip rings with a split ring and connecting a battery
• B. split ring with slip rings and connecting a battery
• C. a.c. with d.c. source and connecting slip rings
• D. a.c. with d.c. source and connecting split rings

A diverging lens of focal length 30cm produces an image 20cm from the lens. Determine the object distance

• A. 10cm
• B. 12cm
• C. 50cm
• D. 60cm