MCQs

Explanation
Dogs can hear sounds in the range of 67 Hz to 45,000 Hz , which is slightly higher than the human audible range.

Explanation
Whales have a unique audible range that is adapted to their underwater environment. They can hear sounds at very low frequencies , often below 20 Hz, and up to 31 kHz.

Explanation
Elephants can hear sounds in the range of 16 Hz to 20,000 Hz.

Explanation
Echoes are repeating sounds that are reflected back to the listener after the original sound has stopped. They are a result of sound waves bouncing off a surface and returning to the listener , creating a repeated or echoic effect.

Explanation
The speed of sound in diamond is approximately 12,000 meters per second (m/s). It is one of the fastest speeds of sound among all materials. The speeds of sound in different materials: Air: 343 m/s Water: 1433 m/s Wood: 3300-3600 m/s Brick: 4176 m/s Steel: 6100 m/s Diamond: 12000 m/s

Explanation
The speed of sound in air at sea level and 20°C (68°F) is approximately 343 meters per second . The speeds of sound in different materials: Air: 343 m/s Water: 1433 m/s Wood: 3300-3600 m/s Brick: 4176 m/s Steel: 6100 m/s Diamond: 12000 m/s

Explanation
Sound travels slowest in air , with a speed of approximately 343 meters per second (m/s) at 20°C. This is because air is a gas and has a low density and stiffness , which allows sound waves to propagate more slowly through the material. The speeds of sound in different materials: Air: 343 m/s Water: 1433 m/s Wood: 3300-3600 m/s Brick: 4176 m/s Steel: 6100 m/s Diamond: 12000 m/s

Explanation
The velocity of a wave (v) is equal to the product of its wavelength (λ) and frequency (f). This is expressed mathematically as: v = λf

Explanation
Primary Cause of 2022 Floods : Record Monsoon Rains : Pakistan received 190% more rainfall than average (NDMA data), submerging 1/3 of the country. Glacial Melt : Heatwaves accelerated melting, adding to water volume (UN report). Poor Infrastructure : Weak dams, drainage systems, and urban planning worsened flooding.

Explanation
The local government system brings governance closer to the people, allowing for faster and more responsive service delivery. It helps decentralize power from federal/provincial levels and encourages community participation in development.