Explanation

Nuclear fusion reactions in a star's core produce outward thermal pressure, which balances the inward pull of gravity.

This balance between gravitational force and nuclear pressure keeps the star stable and prevents collapse during its main life phase.

Explanation

An electrostatic precipitator is a device used in factories and power plants to remove dust and smoke particles from exhaust gases.

It helps in air pollution control by using electrical charges to attract and collect harmful particles.

Explanation

Sound travels faster in solids than in liquids and gases due to the closer arrangement of particles in solids.

Iron, being a solid, allows sound to travel faster compared to air and water.

Explanation

The moon's orbit is tilted about 5 degrees relative to the Earth's orbit around the sun.

This tilt means that the Earth, moon, and sun do not align perfectly every month, preventing a lunar eclipse from occurring monthly.

Explanation

A refrigerator transfers heat from inside to outside using thermodynamic cycles.

It relies on principles like heat absorption, compression, and expansion of refrigerants.

Explanation

Sputnik-1, launched by the Soviet Union in 1957, was the first artificial satellite to orbit the Earth.

It marked the beginning of the space age and the start of space exploration.

Explanation

When current flows through a bulb, electrical energy is converted into both heat and light energy.

The filament inside the bulb heats up due to resistance (Joule heating) and emits light as a result.

Explanation

Pigeons have a hearing range of approximately 45Hz to 7000Hz, allowing them to detect low-frequency sounds.

This ability helps them navigate and sense environmental changes, such as approaching storms.

Explanation

An opaque object does not allow light to pass through.

A wooden box blocks light completely, making it opaque.

Explanation