Position, path length and displacement MCQ Quiz in मल्याळम - Objective Question with Answer for Position, path length and displacement - സൗജന്യ PDF ഡൗൺലോഡ് ചെയ്യുക

CONCEPT:

• The motion of an object is said to be translatory if the position of the object is changing with respect to a fixed point or object.
• For example: Car moving on a road, moving trains, etc.
• All the particles of a body executing translatory motion move in the same direction traversing parallel paths.

EXPLANATION:

• As the motion of the train is an example of a translatory. So option 4 si correct.

CONCEPT:

• One-dimensional motion: When a body is moving on a straight line then it is called one-dimensional motion.
  • Example: Moving train, body moving on a straight line like a horse, boy, etc.
• Two-dimensional motion: The body moving on a zig-zag path of two dimensions, circular motion, or a projectile motion are a two-dimensional motion.

EXPLANATION:

• A train running on a straight track is an example of one-dimensional motion. Rest all others are two or three-dimensional motion. Hence option 1 is correct.

The correct answer is zero

Key Points

• For a body in circular motion, the displacement of the object is equal to the length of the shortest path between the final and the initial points. 
• If the body comes back to its original position, then the displacement of the body is zero.
• In this case, the body completes two revolutions along the circular path.
• Therefore, it returns to its initial position after completing one revolution. 
• Hence, the displacement of the body is zero.

Additional Information

Displacement:

• It is the shortest distance covered by a body in a definite direction.
• It is a vector quantity.
• It can be positive, Negative or Zero.
• The unit of displacement is a meter(m).

The correct answer is A, B and D.

Explanation:

A. Distance - time graph of a body at rest:

• This graph would be a straight horizontal line at the distance axis, showing that the body is not changing its position over time.

B. Velocity - time graph of a body moving with uniform acceleration:

• This graph would be a straight line inclined upwards or downwards, indicating a constant change in velocity over time due to uniform acceleration.

C. Distance - time graph of a body moving with uniform acceleration:

• This graph would be a curve, not a straight line. The slope of the curve would change, indicating the changing velocity due to uniform acceleration.

D. Velocity - time graph of a body at rest:

• This graph would be a straight horizontal line at the velocity axis, showing that the body's velocity remains constant (which is zero in this case) over time.

Hence, the correct options are A, B, and D.

The correct answer is option 4) i.e. zero

CONCEPT:

• Distance refers to the total path covered by an object during its motion or during a time interval.
  • The SI unit of distance is meter (m).
  • It is a scalar quantity and thus, has only magnitude.
• Displacement is the distance between the initial and final position after the motion or journey of an object.
  • Displacement is a vector quantity and can be obtained from the difference of position coordinates of the initial and final positions.

CALCULATION:

Distance covered by the athlete in one round, D = 2πR

Time taken for one round, t = 20 s

Speed of the athlete, s = D/t = 2πR/20

Distance covered in 2 min 20s i.e. 140 s will be = s × time = \(\frac{2\pi R}{20} \times 140 = 14\pi R\)

Number of rounds completed in 140 s = \(\frac{14\pi R}{2\pi R} = 7\)

• As the athlete completes 7 complete rounds, she will be at the starting point once again.
• Hence, displacement is zero.

The correct answer is option 3) i.e. It may or may not be equal to the distance

CONCEPT:

• Distance refers to the total path covered by an object during its motion or during a time interval.
  • The SI unit of distance is meter (m).
  • It is a scalar quantity and thus, has only magnitude.
• Displacement is the distance between the initial and final position after the motion or journey of an object.
  • Displacement is a vector quantity and can be obtained from the difference of position coordinates of the initial and final positions.

EXPLANATION:

• Displacement can be zero either when the particle is stationary or when the particle has returned to its starting position during its journey.
• Displacement cannot be greater than the distance travelled by an object as it is the shortest distance between two points.
• However, it may or may not be equal to distance. In a straight line forward motion, the distance equals displacement.

The correct answer is option 2) i.e. The body is stationary

CONCEPT:

• Distance refers to the total path covered by an object during its motion or during a time interval.
• The SI unit of distance is meter (m).
• It is a scalar quantity and thus, has only magnitude.
• Displacement is the distance between the initial and final position after the motion or journey of an object.
• Displacement is a vector quantity and can be obtained from the difference of position coordinates of the initial and final positions.

EXPLANATION:

• The representation for the displacement-time graph of a body parallel to the x-axis is as shown.

• Here, it can be inferred that the value of displacement remains the same at every instant of time.
• This indicates the body is no more under motion and is, therefore, stationary or at rest.

CONCEPT:

Displacement:

• It is the shortest distance between the initial and final positions of the particle.
• It is a vector quantity.

Distance:

• Distance is defined as the total length of the path covered by the body.
• It is a scalar quantity.

EXPLANATION:

• When the object moves in a straight line without changing the direction of motion its displacement will be equal to the distance.
• If the object changes its direction of motion, its displacement will be less than the distance covered.
• So we can say that the displacement of the body is always less than or equal to the distance covered by the body.
• Hence, option 2 is correct.

• The magnitude of displacement is equal to the minimum possible distance between two positions. So distance ≥ Displacement.
• For a moving particle, distance can never be negative or zero while displacement can be (Zero displacement means that body after motion has come back to initial position). i.e., Distance > 0 but Displacement > = or < 0.
• For motion between two points displacement is single-valued while distance depends on the actual path and so can have many values.
• For a moving particle, distance can never decrease with time while displacement can.
• A decrease in displacement with time means the body is moving towards the initial position.

The correct answer is option 3)

CONCEPT:

Displacement 

• It is the distance between the initial and final position after the motion or journey of an object.
• Displacement is a vector quantity and can be obtained from the difference of position coordinates of the initial and final positions.

EXPLANATION:

• In uniform motion, an object covers equal distances in equal intervals of time i.e. the position of the object changes uniformly with time.
• Among the given graphs this is correctly represented by option 3).
• The graph in option 1) is a plot for displacement vs time when the object is stationary.
• The graph in option 2) and 4) shows non-uniform motion.

The correct answer is option 1) i.e. Zero

CONCEPT:

• Displacement is the distance between the initial and final position after the motion or journey of an object.
  • Displacement is a vector quantity and can be obtained from the difference of position coordinates of the initial and final positions.

EXPLANATION:

• The lady starts the journey from her home (initial point) and reaches back to her home (final point) upon seeing the shop closed. Here, the initial and final point at the end of the journey is the same. Hence, the displacement is zero.