10th Class Physics Second half Book Paper

Q1. Multiple choice questions (Attempt all · 12 × 1 = 12)

1. The induced current generated according to Lenz’s law always:
   1. Supports the motion of the magnet
   2. Opposes the motion of the magnet
   3. Stops the magnet
   4. Moves randomly
2. To avoid thermal noise, qubits are cooled to within a few thousandths of a degree of:
   1. 0°C
   2. 100°C
   3. Absolute zero
   4. Boiling point of water
3. Electricity ensures our devices remain functional by:
   1. Cooking food
   2. Recharging batteries
   3. Cooling the environment
   4. Producing light
4. The usual range of ammeters for home appliances is:
   1. 1 A to 10 A
   2. 1 A to 100 A
   3. 100 A to 500 A
   4. Less than 1 A
5. The natural emission of radiations from unstable nuclei is called:
   1. Fusion
   2. Fission
   3. Radioactivity
   4. Ionization
6. The phenomenon of blue sky and red sky is explained by:
   1. Dispersion of light
   2. Polarization of light
   3. Scattering of light
   4. Reflection of light
7. When the switch in relay is ON:
   1. Lamp remains OFF
   2. Current stops
   3. Lamp glows
   4. Armature is disconnected
8. In an NPN transistor under normal operation, the emitter-base junction is:
   1. Reverse biased
   2. Forward biased
   3. Neutral
   4. Insulated
9. A thermistor is generally made from:
   1. Metal wire
   2. Semiconductor material
   3. Plastic
   4. Glass
10. Conventional current flows:
    1. From positive to negative terminal
    2. From negative to positive terminal
    3. In both directions
    4. In random motion
11. Which radioactive element is commonly used in smoke alarms?
    1. Uranium-235
    2. Cobalt-60
    3. Americium-241
    4. Iodine-131
12. Prolonged exposure to infrared waves can cause:
    1. Hearing loss
    2. Thermal damage and burns
    3. Muscle cramp
    4. Bone fracture