Explanation

• Weight is a vector quantity
• Because it is a force defined as the product of mass and the acceleration due to gravity (W = mg).
• It has both magnitude (amount of force) and direction (downward, towards the center of the Earth)

Additional information 

Mass,  Time, and temperature are scalar quantities

Last updated on 09-03-2026

Explanation

Scalar quantities are physical quantities that have only magnitude (amount or size) but no direction.

Examples of scalar quantities include:

• Mass
• Temperature
• Time
• Energy
• Distance

Last verified on 07-02-2026

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

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.

Explanation

Efficiency is the ratio of output to input, often expressed as a percentage.

It represents how much of the input energy is actually converted into useful output energy, with the rest being lost as waste or heat.

Key Points:

• Energy is the ability to do work.
• Work is the transfer of energy through a force applied over a distance.
• Power is the rate at which work is done or energy is transferred.

Explanation

Heat is a form of energy, specifically thermal energy, which is transferred from one body to another due to a temperature difference.

It is a type of kinetic energy, where the particles of a substance vibrate or move rapidly, generating heat.

Explanation

A body is in equilibrium when the net force acting on it is zero, and it is not changing its motion.

This means that the body is either at rest or moving with a constant velocity (uniform speed), but not accelerating.

Explanation

Power is the work done per unit time, measured in watts (W).

It represents the rate at which energy is transferred or work is done.

Additional Information:

• Efficiency is the ratio of output to input energy.
• Energy is the ability to do work.
• Force is a push or pull that can cause an object to change its motion.