CBSE Class 9 - Physics - Motion - Assignment Sheet (#cbseNotes)

Physics - Motion

Class-IX

Assignment Sheet

Q1(MCQs) : Choose the correct option from choices given.

ⅰ A particle is moving in a circular path of radius’ r’. The displacement after half a circle would be
(a) Zero
(b) π × r
(c) 2r
(d) 2 × π × r

ⅱ The numerical ratio of displacement and distance of a moving object is
(a) always greater than 1.
(b) always equal to 1.
(c) always more than 1.
(d) equal or less than 1.

ⅲ An object has moved through a finite distance
(a) its displacement must be equal to the distance moved by it.
(b) its displacement must be positive .
(c) its displacement is less than the distance moved by it.
(d) Displacement may be zero.



ⅳ Speedometer fitted in an automobile measure its
(a) average speed
(b) acceleration
(c) instantaneous speed
(d) distance covered

ⅴ An object is said to have a variable velocity if
(a) its speed changes
(b) its direction of motion changes
(c) its speed as well as direction of motion changes.
(d) all of the above

Q2: Answer the following in brief.

(a) The distance time graph of a particle is a straight line parallel to the time axis, it means that the
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(b) What is the value of acceleration for a body at rest?

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(c) Odometer is an instrument fitted in an automobile measures

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(d) A student considered Earth as point object while considering its motion around the sun, Is he justified?

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(e) What is real meaning of negative acceleration?

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Q3:
ⅰ Draw the graphical representation of motion(on graph paper)
(a) Uniform speed
(b) Non uniform speed

ⅱ Draw the Speed-time graphs for the following:
a) When velocity remains constant
b) Uniform acceleration
c) When initial speed of a body is not zero.
d) Non uniform acceleration


Q4: A car is moving on a straight road with uniform acceleration. The following table gives the speed of the car at various instants of time:

┌───────┬───┬───┬───┬───┬───┬───┬───┐
│ Speed │5  │10 │15 │20 │25 │30 │35 │
├───────┼───┼───┼───┼───┼───┼───┼───┤
│ Time  │0  │10 │20 │ 30│ 40│50 │60 │ 
└───────┴───┴───┴───┴───┴───┴───┴───┘

Draw the speed time graph by choosing a convenient scale. Determine for it:
(a) The acceleration of the car
(b) The distance travelled by the car in 60 seconds?


Q5: Write the differences between:
(a) Distance vs Displacement
(b) Speed vs Velocity


Q6: An object starting from rest covers 20 metres in first 2 seconds & 160 metres in next 4 seconds. What is its velocity after 7 seconds from the start?


Q7: A car moving at speed of 72km/h and applies brakes which provide a retardation of 5m/s².
ⅰ How much time does the car take to stop?
ⅱ How much distance does the car cover before coming to rest?
ⅲ What would be the stopping distance needed if speed of the car is doubled?