Explanation

The mass of Earth is approximately 6.0 x 10^24 kilograms (5.98 x 10^24 kg).

This is a widely accepted scientific value, based on various measurements and calculations, including:

• Gravity measurements
• Satellite orbits
• Seismological data
• Planetary formation models

Explanation

• The shortest distance between two points is called displacement.
• Displacement is a measure of the straight-line distance between two points.
•  It is a vector quantity.

Key Point: The longest distance between two points is called the circumference (if the points are on a circle) or a diagonal (if the points are on a polygon or a rectangle).

Explanation

Neutral equilibrium is a state where the body is balanced, but the slightest disturbance will not cause it to return to its original position or topple over.

In this state, the center of gravity (CG) remains at the same height, regardless of the slight tilt or displacement.

Key Points: 

• A body is in unstable equilibrium after slight tilt if its center of gravity remains above the point of contact.
  
• A body is in stable equilibrium after slight tilt if its center of gravity remains above the point of contact.
  

Explanation

The melting point of ice at normal atmospheric pressure is 0 °C (zero degrees Celsius).

Key Points:

• 0 K (zero Kelvin) is equivalent to -273.15 °C, which is absolute zero, the lowest possible temperature.
• 100 °C is the boiling point of water at normal atmospheric pressure.

Explanation

The SI unit of acceleration is meters/second^2 (m/s^2 or ms^-2)

Acceleration (a) is defined as the rate of change of velocity.

Velocity is a vector quantity, and therefore acceleration is also a vector quantity.