Physics Unit Quiz

Which of the following has no unit –

• Density

• Relative density

• Displacement

• Pressure

Answer explanation

Relative density is a ratio of densities and is dimensionless, meaning it has no unit. In contrast, density, displacement, and pressure all have specific units associated with them.

Ampere second is the unit of –

• Charge

• Power

• Voltage

• Energy

Answer explanation

Ampere second is the unit of electric charge, also known as coulomb. It quantifies the amount of electric charge transferred by a constant current of one ampere in one second, making 'Charge' the correct answer.

Gallon is generally used for –

• For velocity

• For a container

• For measuring the volume

• None of these

Answer explanation

A gallon is a unit of measurement specifically used for measuring volume, commonly for liquids. Therefore, the correct choice is 'For measuring the volume'.

Which unit is used for measuring Astronomical distance?

• Pedometer

• Parsec

• Light year

• Length of Hubble

Answer explanation

The correct unit for measuring astronomical distances is the light year, which is the distance light travels in one year. While parsecs are also used, the question specifically highlights light years as the primary unit.

S.I. unit of pressure is –

• Newton/cm2

• Newton-m2

• Newton/m2

• Newton-cm2

Answer explanation

The S.I. unit of pressure is defined as force per unit area. Therefore, the correct unit is Newton/m2, which represents Newtons applied over a square meter. Other options do not correctly represent this relationship.

What is the SI unit of pressure?

• Pascal

• Radian

• Ampere

• Steradian

Answer explanation

The SI unit of pressure is the Pascal (Pa), which is defined as one newton per square meter. The other options, such as radian, ampere, and steradian, represent different physical quantities and are not units of pressure.

Nm-2 is S.I. unit of –

• Force

• Repulsion

• Momentum

• Pressure

Answer explanation

Nm-2 is the unit of pressure in the SI system, representing force per unit area. It is not a unit for force, repulsion, or momentum, making pressure the correct answer.

The unit of approximate distance from the earth to the sun is –

• Light year

• Astronomical Unit

• Kelvin

• Joule

Answer explanation

The correct answer is 'Astronomical Unit' (AU), which is the standard unit of measurement for the average distance from the Earth to the Sun, approximately 93 million miles or 150 million kilometers.

S.I. unit of force is -

• Kelvin

• Newton

• Pascal

• Volt

Answer explanation

The S.I. unit of force is the Newton, named after Sir Isaac Newton. It is defined as the force required to accelerate a one-kilogram mass by one meter per second squared.

What is the SI unit of force?

• Newton

• Dyne

• Pascal

• Kip

Answer explanation

The SI unit of force is the Newton, named after Sir Isaac Newton. It is defined as the force required to accelerate a one-kilogram mass by one meter per second squared, making it the correct choice among the options.