Motion & Measurement of Distances

Identify the correct answer from the hints: This type of motion occurs when different parts of an object move at varying distances from a central axis, while the object itself remains stationary.

1. Revolutionary motion
2. Translational motion
3. Rotational motion
4. Oscillatory motion

Answer: (c) Rotational motion

Which of the following statements are incorrect about periodic motion? A) A pendulum always swings with increasing speed. B) Periodic motion repeats at regular intervals. C) The swing in a playground is a form of periodic motion. D) Periodic motion has no specific starting point.

1. A and B
2. B and C
3. C and D
4. A and D

Answer: (d) A and D

An astronaut carries a toolbox with a mass of 20 kg on Earth. She takes it to the International Space Station. She notices that the toolbox floats, but still feels some effort is required to stop or move it. What is the best explanation of this observation?

1. The mass of the toolbox becomes zero in space.
2. The weight of the toolbox is zero in space.
3. The toolbox is weightless and massless in space.
4. n space, both mass and weight change depending on temperature.

Answer: (b) The weight of the toolbox is zero in space.

A tailor uses a sewing machine to stitch a shirt. Which of the following correctly represents the combination of motions involved in the functioning of the sewing machine's needle and the wheel?

1. Needle – Vibratory, Wheel – Translational
2. Needle – Oscillatory + Periodic, Wheel – Rotational
3. Needle – Periodic + Translational, Wheel – Rotational
4. Needle – Oscillatory, Wheel – Circular

Answer: (b) Needle – Oscillatory + Periodic, Wheel – Rotational

You are given three objects to measure their masses: Object A: A fruit (apple) Object B: A small metal piece Object C: A book Which of the following devices is best suited for measuring the mass of each object?

1. A beam balance for all objects
2. A spring balance for all objects
3. An electronic balance for Object A and Object B, and a beam balance for Object C
4. An electronic balance for Object A, a spring balance for Object B, and a truck scale for Object C

Answer: (c) An electronic balance for Object A and Object B, and a beam balance for Object C

Which of the following statements about oscillatory and periodic motion are correct? 1. All periodic motions are oscillatory motions. 2. All uniform motions are periodic motions. 3. A child rocking on a swing is an example of both oscillatory and periodic motion. 4. The motion of a clock's second hand is periodic but not oscillatory.

1. 1 and 3
2. 2 and 4
3. 3 and 4
4. 1 and 2

Answer: (c) 3 and 4

Match the type of motion with its characteristics and examples: Column A – Type of Motion Column B – Combined Characteristics Column C – Real-World Application Example A) Translational + Curvilinear 1) Motion where all parts move same distance, but along a curved path a) A car turning along a curved flyover B) Oscillatory + Periodic 2) Repeats motion to and fro at fixed time intervals about a mean position b) A pendulum swinging in a clock C) Rotational + Periodic 3) Spinning around a fixed axis with equal time intervals per revolution c) Second hand of a clock D) Translational + Rectilinear 4) Body moves forward in a straight line without any rotation or curve d) Luggage moving on a straight airport conveyor belt

1. A-1-a, B-2-b, C-3-c, D-4-d
2. A-2-a, B-3-b, C-1-c, D-4-d
3. A-3-a, B-1-b, C-2-c, D-4-d
4. A-1-d, B-3-b, C-2-c, D-4-a

Answer: (a) A-1-a, B-2-b, C-3-c, D-4-d

A gymnast performing on a horizontal bar exhibits different types of motion. Identify the incorrect statement regarding her movements.

1. When she spins around the bar, she exhibits rotational motion
2. As she swings back and forth, her motion is oscillatory
3. When she moves from one end of the bar to another, she undergoes translatory motion
4. When she jumps off the bar, she exhibits vibratory motion

Answer: (d) When she jumps off the bar, she exhibits vibratory motion

In the diagram, a ceiling fan is switched on, a keychain swings from one of its blades, and the fan rotates. Identify all types of motion occurring in the keychain.

1. Circular + Periodic + Oscillatory
2. Rotational + Vibratory
3. Circular + Oscillatory
4. Circular + Translational + Periodic

Answer: (a) Circular + Periodic + Oscillatory

Lesley and John placed an irregularly shaped object on a graph paper with 1 cm² squares. The object covered 30 full squares and 10 partial squares, each approximately half-filled. Lesley calculated the area as 35 cm², while John calculated it as 40 cm². They were trying to estimate the area of a leaf for a biology project. Who is more accurate in estimating the area and why?

1. Lesley is correct as she added only half of the partially covered squares.
2. John is correct as he considered all partially filled squares.
3. Lesley is incorrect as she ignored the uneven edges of the leaf.
4. Both are incorrect as the graph paper method cannot be used for measuring irregular shapes.

Answer: (a) Lesley is correct as she added only half of the partially covered squares.