Explanation

• When light is focused in front of the retina, it creates a blurred image, indicating nearsightedness (myopia).
• This occurs because the eyeball is too long or the cornea is too steep.
• It causing light to focus before reaching the retina.

Last verified on 16-03-2026

Explanation

KE = 0.5mv² = 0.5 × 0.25 kg × (20 m/s)² = 0.5 × 0.25 × 400 = 50 J

Last verified on 16-03-2026

Explanation

The renewable energy sources are:

• Water energy
• Wind energy
• Tidal energy
• Solar energy
• Hydroelectric
• Ocean energy
• Geothermal energy
• Biomass
• Biogas

The non-renewable energy sources are:

• Fossil fuels or Hydrocarbon fuel (Oil, Natural gas, Coal)
• Nuclear energy

Last verified on 16-03-2026

Explanation

• Gear is a wheel with teeth along its edge that interlock with another gear to transmit motion and force.
• Gears are used to increase or decrease speed, change direction, or increase torque in machines.
• Common in clocks, bicycles, vehicles, and industrial machines.

Last verified on 16-03-2026

Explanation

• 1 meter = 3.2808 feet exactly.

Additional information:

• 1 kilometer = 3280.8 feet
• 1 centimeter = 0.032808 feet
• 1 inch = 0.083333 feet
• 1 mile = 5280 feet
• 1 yard = 3 feet

Last verified on 16-03-2026

Explanation

Explanation

• A solar day is the time taken by the Earth to complete one full rotation on its axis relative to the Sun.
• Length of a solar day = 24 hours = 1,440 minutes
• Length of a sidereal day = 23 hours 56 minutes 4 seconds
• Earth rotates approximately 360° relative to the Sun in a solar day
• Lunar day = ~24 hours 50 minutes (Moon’s rotation relative to Sun)

Last verified on 15-03-2026

Explanation

• Momentum (p) = Mass × Velocity
• A heavier object (like a car) usually has more momentum at the same speed.
• A lighter object (like a bullet) can have more momentum if its velocity is extremely high.

Examples

• Car: Mass = 1000 kg, Speed = 20 m/s → p = 20,000 kg·m/s
• Bullet: Mass = 0.01 kg, Speed = 800 m/s → p = 8 kg·m/s
• Motorcycle: Mass = 200 kg, Speed = 30 m/s → p = 6,000 kg·m/s

Last verified on 15-03-2026

Explanation

• The iris is the colored part of the eye that controls the size of the pupil.
• By adjusting the pupil size, it regulates the amount of light entering the eye, just like a camera diaphragm.
• Pupil dilation occurs in low light, letting in more light.
• Pupil contraction occurs in bright light, protecting the retina from damage.

Last verified on 15-03-2026

Explanation

• According to Newton’s Second Law of Motion: Force (F) = Mass (m) × Acceleration (a)
• It shows that the force applied on an object is proportional to its mass and acceleration.

Additional information:

• Unit of Force – Newton (N)
• 1 N = 1 kg·m/s²

Last verified on 15-03-2026