Physical Quantities MCQ Quiz - Objective Question with Answer for Physical Quantities - Download Free PDF

The Correct Answer is Silver.

Key Points

• The resistivity of Silver is 1.59×10⁻⁸ Ω⋅m.
• Silver is a chemical element with the atomic number 47 and the symbol Ag.
• It is a lustrous, soft, white transition metal with the highest electrical conductivity, thermal conductivity, and reflectivity of any metal.
• The metal can be found in its pure, elemental form in the Earth's crust, as an alloy with gold and other metals, and in minerals like argentite and chlorargyrite.
• The majority of silver is produced as a byproduct of the refining of copper, gold, lead, and zinc.

Important Points

• Electrical resistivity is a property that determines how well a material absorbs electric current.
• Electrical conductivity, its opposite, is a measurement of how well a substance conducts electricity. A material with a low resistivity allows electric current to pass through it easily. 
• The Greek letter ρ (rho) is used to represent resistivity.

Additional Information

AC resistance is also known as Impedance.

Key Points

• In electrical engineering, electrical impedance is a measure of the resistance of the circuit to the current when the voltage is applied.
• Quantitatively, the impedance of the two-terminal circuit element is the ratio of the complex representation of the sinusoidal voltage between its terminals to the complex representation of the current flowing through them.
• Impedance is a complex number, with the same units as resistance, for which the ohm is the SI unit.
• The symbol is usually Z and can be represented by writing its magnitude and phase in the polar form However, the representation of Cartesian complex numbers is often more powerful for circuit analysis purposes.

The correct answer is Columb.

Key Points

• A Coulomb is defined as the amount of electric charge transported by one ampere current in one second from one point to another..
• Columb is used to measure the amount of Electric charge.  
• Electric charge: 
  • Electric charge is a general property of protons, electrons, and subatomic particles.
  • Protons are positively charged while electrons are negatively charged.
  • Similar charges repel each other whereas opposite charges attract each other.

Additional Information

• ​Luminous intensity:
  • Luminous intensity is calculated the weighted power of wavelength, transit by a source of light in any specific direction per unit solid angle.
  • It depends on the luminosity function, a standardized phenomenon of the sensitivity of the human eye.
  • The SI unit of luminous intensity is Candela.
• Volt: 
  • Volt(V) is the unit of Electric voltage or electric potential difference.
  • One Volt is described as the consumption of energy of one joule per electric charge of one coulomb.

The Correct Answer is Velocity.

• The physical quantities which are specified with the magnitude or size alone are called scalar quantities. For example, length, speed, work, mass, distance, entropy, energy, etc.
• Vector quantities refer to the physical quantities characterized by the presence of both magnitude and direction. For example, velocity, displacement, force, torque, momentum, acceleration, etc.

The correct answer is Mass.

Key Points

• Mass is a scalar quantity because it has only magnitude and no direction.
• Scalar quantities are those physical quantities that are described completely by their magnitude alone.
• Unlike vectors, scalar quantities do not require direction for their specification.
• Mass is a fundamental property of matter and is independent of the object's location or the forces acting upon it.
• Examples of scalar quantities include mass, temperature, energy, and distance.

Additional Information

• Velocity:
  • Velocity is a vector quantity as it has both magnitude and direction.
  • It represents the rate of change of an object’s position with respect to time.
• Momentum:
  • Momentum is a vector quantity given by the product of an object’s mass and its velocity.
  • It indicates the amount of motion an object has and the direction of that motion.
• Force:
  • Force is a vector quantity that represents the interaction that causes an object to accelerate.
  • It is described by both magnitude and direction, with the SI unit being the newton (N).
• Scalar vs. Vector Quantities:
  • Scalar quantities are described by magnitude only, while vector quantities require both magnitude and direction.
  • Key examples of scalar quantities: energy, speed, and mass; key examples of vector quantities: displacement, velocity, and force.

The Correct Answer is Velocity.

• The physical quantities which are specified with the magnitude or size alone are called scalar quantities. For example, length, speed, work, mass, distance, entropy, energy, etc.
• Vector quantities refer to the physical quantities characterized by the presence of both magnitude and direction. For example, velocity, displacement, force, torque, momentum, acceleration, etc.

The correct answer is Columb.

Key Points

• A Coulomb is defined as the amount of electric charge transported by one ampere current in one second from one point to another..
• Columb is used to measure the amount of Electric charge.  
• Electric charge: 
  • Electric charge is a general property of protons, electrons, and subatomic particles.
  • Protons are positively charged while electrons are negatively charged.
  • Similar charges repel each other whereas opposite charges attract each other.

Additional Information

• ​Luminous intensity:
  • Luminous intensity is calculated the weighted power of wavelength, transit by a source of light in any specific direction per unit solid angle.
  • It depends on the luminosity function, a standardized phenomenon of the sensitivity of the human eye.
  • The SI unit of luminous intensity is Candela.
• Volt: 
  • Volt(V) is the unit of Electric voltage or electric potential difference.
  • One Volt is described as the consumption of energy of one joule per electric charge of one coulomb.

The correct answer is Acceleration.

Key Points

• Vector Quantity is defined as which quantity has both direction and magnitude.
• It can be represented by an arrow whose direction is the same as that of the quantity and whose length is proportional to the quantity’s magnitude.
• Although, it does not have any position. For example, Acceleration, Displacement, and Velocity are Vector Quantities, while Speed of the magnitude of Velocity, Mass, and Time are Scalars Quantity.
• The Measurement of the Increase or Decrease in the Medium of the temperature is a Vector Quantity. But, the Measurement of the Medium’s Temperature is a Scalar Quantity.
• ​Force and displacement are vector quantities (they have both magnitude and direction) and the dot product of two vector quantites always gives a scalar quantity. So work has only magnitude but not direction. 

The Correct Answer is 7.

Key Points

• The SI consists of 7 base units that describe the 22 units with special names and symbols that are derived. In international trade, the SI plays an important role and is widely used in scientific and technical research and development.
• The modern form of the metric system is the International System of Units (SI). In almost every nation in the world, it is the only method of measurement with official status.
• It consists of a coherent system of measurement units beginning with seven base units, the second (unit of time with the symbol s), the meter (length m), the kilogram (mass, kg), the ampere (electric current, A), the kelvin (thermodynamic temperature, K), the mole (substance quantity, mol) and the candela(luminous intensity, cd).

Important Points

The Correct Answer is Option 2 i.e stoke.

The correct answer is Speed.

Key Points

• The speed of an object is the amount of the change of its position; thus, it is a scalar quantity.
• The average speed of an object in an interval of time is the distance travelled by an object measured by the length of the interval; the instantaneous speed is the limit of the average speed as the period of the time interval reaches zero.
• Speed has the dimension of the distance separated by time.
• The SI unit of speed is meter per second.

Important Points

• The pressure is the force applied perpendicular to the surface of the target per unit area over which the force is distributed.
• Motion is a mechanism in which an object has shifted its location over time.
  • Motion is mathematically defined in terms of displacement, space, direction, acceleration, speed, and time.
• Acceleration is the rate of change in the velocity of an object with respect to time.
  • Accelerations are vector quantities (in that they are of magnitude and direction).

The correct answer is option 4.

Important Points

Celsius and Fahrenheit's temperatures show the same value at -40°.

The conversion formula for Celsius to Fahrenheit is given by:

\(F={9\over5}C +32\)

To find the temperature where both Fahrenheit and Celsius temperatures are equal let \(F=C=x\)

Substituting these values in the equation above we get

\(x-{9\over5}x=32 \)

\({5x-9x\over5}=32\)

\({-4x\over 5}=32\)

\(x=-{5\over 4}\times32=-{160\over4}=-40\)

Therefore -40º is the temperature where Both Celsius and Fahrenheit read the same.

• There are four scales of temperature are Fahrenheit, Celsius, Kelvin, and Rankine.
• When following SI units, Temperature is measured in Kelvins.
• The lower possible temperature that can be achieved is -273.15ºC or 0K and is called absolute zero.

The correct answer is Area.

Key Points

• Thrust is defined as the force acting perpendicular to the surface of an object.
• The formula of thrust
  •  Thrust=Pressure∗Area" id="MathJax-Element-37-Frame" role="presentation" style="position: relative;" tabindex="0">Thrust=Pressure∗AreaThrust=Pressure∗Area $Thrust = Pressure * Area$   

​ Additional Information

• Mass is defined as the amount of matter in a substance.
• Density is defined as the ratio of the mass per unit volume.
• Volume is defined as the quantity of three-dimensional space occupied by a liquid, solid, or gas.

 The correct answer is 11.2 km/sec.

Key Points

• Escape velocity is the lowest velocity which a body must have to escape the gravitational attraction of a particular planet or other objects.
• The escape velocity of Earth is 11.19 kilometre per second.
• The escape velocity of Venus is 10.36 km per second.
• The escape velocity of Mars is 5.03 km per second.
• The escape velocity of Saturn is 36.09 km per second.

The correct answer is Option 2, i.e 10 ohm.

• Given that two resistors of 20 ohms are connected in parallel.
• So, the resultant resistance
• 1/R_c = 1/R₁ +1/R₂ = 1/20 + 1/20 = 1/10 ohm
• So, R_c = 10 ohm
• A voltage source offers very minimal resistance. Hence, the total resistance is 10 ohms.