Study Matrix

Definition

Position Change Over Time

Examples from Text

Does not change its position with time in relation to its surroundings.

No

• A chair kept on the floor• A tree rooted to the ground• A transmission tower fixed to the ground

Changes its position with time with respect to its surroundings.

Yes

• A bus moving past a person on the road• A walking camel• A flying bird• A soccer player kicking a football

Definition

Path of Movement

Examples from Text

The motion of an object along a straight line.

Straight line

• A car moving along a straight road• A ball falling down in a straight path• An athlete running on a straight racing track• A coin moving undeflected over a carrom board• A bullet fired from a gun

The motion of an object along a curved line.

Curved line

• A car taking a turn on a road• A javelin thrown by an athlete• A basketball thrown into the basket• A train moving along a curved track

Definition

Movement of Points on the Body

Examples from Text

The motion of an object about a fixed central point along the circumference of a circle.

Every point moves along the circumference of a circle around a central point.

• A girl swinging a ball tied to a string in a circular path• The motion of children on a merry-go-round• Children running on a circular track

The motion of a body about a fixed axis.

Different points move through different distances in the same interval of time (points farther from the axis travel a larger distance than points nearer to the axis).

• A spinning top• A spinning wheel• A rotating fan• A merry-go-round• A potter’s wheel• The hands of a clock• The Earth spinning on its axis

Oscillatory Motion

Vibratory Motion

The whole body moves from one place to another in a to and fro motion about its mean position.

The whole body does not move from one place to another; only parts of the body move about their mean positions.

There is no physical change in the shape of the body.

There is a physical change in the shape of the body.

The distance traversed by the body on either side of the mean position is equal.

The distance traversed by the body on either side of the mean position may not be equal.

Always takes place in a straight line.

Can take place in any direction.

• The motion of a pendulum• The motion of a swing• The motion of a mass suspended by a string• The motion of the piston of an engine

• Plucking of strings of a guitar or a sitar• Playing a drum or tabla• Movement of vocal chords while speaking or singing• Vibration of a car body when the engine is started

Definition

Time Interval Regularity

Examples from Text

The motion which repeats itself at fixed intervals of time.

Regular (repeats at fixed intervals)

• The pendulum of a wall clock (repeats every 2 seconds)• The hands of a clock (hour hand every 12 hours, minute hand every 60 minutes, second hand every minute)• The Earth’s rotation around its axis (every 24 hours)• The Earth’s revolution around the sun (every 365¼ days)

The motion which does not repeat itself at fixed intervals of time.

Irregular (does not repeat at fixed intervals)

• The swinging of arms or legs while walking• The motion of the wheels of a car moving on a busy road where brakes are applied• The motion of a rolling ball which gradually slows down and finally stops on the ground

Uniform Motion

Non-Uniform Motion

An object covers equal distances in equal intervals of time.

An object covers unequal distances in equal intervals of time.

The object moves with a uniform (constant) speed.

The object moves with a non-uniform (variable) speed.

• A car covering 20 km in every 30 minutes• A car covering 30 km in every hour of its journey

• A car starting from rest and covering different distances in every 30 minutes• The motion of a train as it approaches a station where it has to stop• The motion of a ball rolling on the ground• The motion of a fast-moving car when brakes are applied

Primary Function

Units Displayed

Displays the speed of a moving vehicle.

Not mentioned in text

Displays the distance travelled by the vehicle.

Kilometres (km)

Mass

Weight

The amount of matter contained in a body.

The force with which the Earth attracts a body towards its centre.

A constant quantity which does not change from place to place.

Not a constant quantity; varies from place to place depending on the gravitational force.

Can never be zero.

Can be zero if no force of gravity acts on it.

Kilogram (kg).

Newton (N).

Not mentioned in text

Kilogram force (kgf), gram force (gf).

Beam balance or physical balance.

Spring balance.

Remains constant on Earth, Moon, and space.

• Maximum at the poles and minimum at the equator.• Decreases as height increases from the surface of Earth.• Varies depending on the mass of the celestial body (e.g., lower on the Moon than on the Earth).• Becomes zero (weightlessness) when escaping gravity or in free fall.