Practice Measurement and si units - general science mcq Online Quiz (set-1) For All Competitive Exams

Q-1)   In SI units the number of basic physical quantities are

(a)

(b)

(c)

(d)

Q-2)   In the system shown, the masses are released from rest. What shall be the acceleration of the moving masses ?

measurement motion question answer 38

(a)

(b)

(c)

(d)

Q-3)   A stone is thrown vertically upwards with an initial velocity u from the top of a tower of height g ${12u^2}/g$ . With what velocity does the stone reach the ground ?

(a)

(b)

(c)

(d)

Explanation:

As already We know that, when a particle is thrown vertically upward with a velocity u from a point A, the particle returns the point A with the same velocity u.

Now, using the fact $v^2=u^2+2gh$, we obtain $v^2=u^2+2g × {12u^2}/{g} ⇒ v^2 = u^2+24u^2$
⇒ v = 5u

Q-4)   One micron represents a length of

(a)

(b)

(c)

(d)

Q-5)   The unit of work is

(a)

(b)

(c)

(d)

Q-6)   A distance of 1 km means

(a)

(b)

(c)

(d)

Q-7)   The SI unit of electrical resistance of conductor is

(a)

(b)

(c)

(d)

Q-8)   Which of the following is not a fundamental unit?

(a)

(b)

(c)

(d)

Explanation:

Fundamental unit:

The SI unit of a fundamental quantity is called a fundamental unit.

There are 7 fundamental quantities and their fundamental units.
The fundamental quantities are Length, Mass, Time, Electric Current, Thermodynamic Temperature, Luminous Intensity, etc.
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Fundamental Quantities
Quantities S.I unit
Mass Kilogram (kg)
Length meter (m)
Time second (s)
Amount of Substance Mole (mol)
Temperature Kelvin (K)
Electric Current Ampere (A)
Luminous intensity Candela (cd)

Also know,

Fundamental Quantity:

An independent physical quantity that cannot be expressed in terms of other physical quantities is called fundamental quantity.
They are conventionally chosen. It is used as a base to get other derived quantities by combining them.

Supplementary units:

The units that are used along with base units to form derived units in the International System are called supplementary units.

Supplementary Quantities
Plane angle radian (rad)
Solid angle steradian (Sr)
Derived Quantities
Force Newton (N)
Work Joule (J), calorie
Pressure Pascal (Pa)
Power Watt (W)

Explanation for the question:

meter (m), kilogram (Kg) and second (s) are the fundamental units of fundamental quantities Length, Mass and Time respectively.

Where Newton (N) is a Derived Quantities.

Q-9)   A passenger in a moving train tosses a five rupee coin. If the coin falls behind him, then the train must be moving with a uniform

(a)

(b)

(c)

(d)

Explanation:

Acceleration is the correct answer.

Acceleration Definition:

the act or process of moving faster or happening more quickly: the act or process of accelerating or ability to accelerate

  • It is the time rate of change of velocity of a body.
  • It is a vector quantity.
  • Its SI unit is m/s2.

The correct explanation for the problem:

When the coin toss, it also has the same velocity as the velocity of the train but during the time, the coin is in the air, the velocity of the train keeps on increasing, and hence it falls behind the passenger.

Definition for other options,

Speed :

Speed is defined as the rate of change of position of an object in any direction. It is measured as the ratio of distance to the time in which the distance was covered. It is a scalar quantity as it has only direction and no magnitude

Deceleration :

A decrease in speed as the body moves away from the starting point is defined as Deceleration. Deceleration is the opposite of acceleration. Deceleration also is known as negative acceleration.

Velocity :

Velocity is the directional speed of an object in motion as an indication of its rate of change in position as observed from a particular frame of reference and as measured by a particular standard of time. Velocity is a fundamental concept in kinematics, the branch of classical mechanics that describes the motion of bodies.

Q-10)   Among the following the derived quantity is

(a)

(b)

(c)

(d)

Q-11)   Match List I (Physical quantity) with List II (Units) and select the correct answer using the codes given below the lists.
List I (Physical quantity) List II (Units)
A. Power 1. kg ms–1
B. Energy 2. kg m2s–1
C. Momentum 3. Nm–2
D. Pressure 4. kW
  5. kWh
Code: (A) (B) (C) (D)

(a)

(b)

(c)

(d)

Explanation:

Q-12)   Match List I (Items) with List II (Unit of length) and select the correct answer by using the codes given below the lists.
List I (Items) List II (Unit of length)
A. Distance between earth and stars 1. Microns
B. Interatomic distances in a solid 2. Angstroms
C. Size of the nucleus 3. Light years
D. Wavelength of infrared laser 4. Fermi
  5. kilometres
Code: (A) (B) (C) (D)

(a)

(b)

(c)

(d)

Explanation:

Q-13)   Match List-I with List-II and select the correct answer using the code given below the lists.
List I (Quantity) List II (Units)
A. High speed 1. Mach
B. Wavelength 2. Angstrom
C. Pressure 3. Pascal
D. Energy 4. Joule
Code: (A) (B) (C) (D)

(a)

(b)

(c)

(d)

Explanation:

Q-14)   1 barrel of oil is equals to which of the following?

(a)

(b)

(c)

(d)

Q-15)   Match List-I with List-II and select the correct answer using the code given below the lists.
List I (Units) List II (Parametric quantities)
A. Watt 1. Heat
B. Knot 2. Navigation
C. Nautical mile 3. Speed of a ship
D. Calorie 4. Power
Code: (A) (B) (C) (D)

(a)

(b)

(c)

(d)

Explanation:

Q-16)   A nanometre is equal to

(a)

(b)

(c)

(d)

Q-17)   An iron ball and a wooden ball of same radius are released from a height ‘h’ in vacuum. Which of the two balls would take more time to reach the ground?

(a)

(b)

(c)

(d)

Explanation:

Since the time of fall of both balls in a vacuum does not depend on the mass of balls, hence, the time taken by both balls will be exactly equal.

Q-18)   What is measured in Cusec?

(a)

(b)

(c)

(d)

Q-19)   If an object undergoes a uniform circular motion, then its

(a)

(b)

(c)

(d)

Q-20)   Light year is the unit of

(a)

(b)

(c)

(d)