In homes, electrical appliances and lamps are connected in parallel because

• A) Parallel connections do not heat up the wires
• B) series connections use high voltage
• C) less current will be used
• D) less voltage will be used

A stone of mass 0.5kg is dropped from a height of 12m. Calculate its maximum kinetic energy. [g = 10ms^-1]

• A. 3.0J
• B. 6.0J
• C. 30.0j
• D. 60.0J

A catapult used to hold a stone of mass 500g is extended by 20cm with an applied force F. If the stone leaves with a velocity of 40m/s, the value of F is

• A. 4.0 x 10²N
• B. 2.0 x 10³N
• C. 4.0 x 10³N
• D. 4.0 x 10⁴N

When an athlete perspires after running, he loses heat through

• A. Evaporation
• B. Conduction
• C. Radiation
• D. Convection

Which of the following is not a component of a d.c. electric motor?

• A. Commutator
• B. Field magnets
• C. Slip rings
• D. Armature

Calculate the time in which 4.8 kJ of energy would be expended when an electric heater of resistance 1.8 x 103Ω is used on a 240 V mains supply. (Neglect heat losses to the surrounding).

• A. 150.0s
• B. 90.0s
• C. 36.0s
• D. 20.0s

Which of the following quantities is not an example of force?

• A. Mass
• B. Tension
• C. Weight
• D. Friction

Whenever light waves are restricted to a specific plane they are said to be

• A. Diffracted
• B. Refracted
• C. Diffused
• D. Plane polarised

A 500W heater is used to heat 0.6kg of water from 25^oC to 100^oC in t₂ seconds. If another 1000W heater is used to heat 0.2kg of water from 10^oC to 100^oC in t, seconds, find \(\frac {t_1}{t_2}\)

• A. 50
• B. 5
• C. 5/4
• D. 1/5

The particles emitted when³⁹₁₉K decay to³⁹₁₉K is

• A. gamma
• B. beta
• C. electron
• D. alpha