CHAPTER 9 STABILITYSUBJECTIVE QUESTIONS9.1 Stability

1 Underline the correct word in the brackets so that each sentence becomes a true statement.

(a) The stability of an object is its ability to [reduce, maintain] its original position.

(b) If an object is [stable, unstable], it will easily topple over.

(c) The weight of an object is due to [magnetic, gravitational] forces acting on it.

(d) An object with a [lower, higher] centre of gravity is more stable.

(e) The stability of an object depends on the position of its centre of gravity and its [base area, shape].

2 Tick for the stable object.

(a)

(b)

(c)

9.2 Importance of Stability

3 Complete the chart below by stating the ways to improve the stability of an object.

OBJECTIVE QUESTIONS9.1 Stability

1 Diagram 1 shows various sizes of cups.

Which of the cups A, B, C and D is the most stable?

2 Diagram 2 shows a vertical piece of card hanging freely from point P.

Diagram 2

Improving stability

(a) (b)

Which of the points A, B, C and D, is most likely the centre of gravity?

3 The stability of an object is influenced byI the object’s massII the base area of the objectIII the position of the object’s centre of gravityA I and II only C II and III onlyB I and III only D I, II and III

4 Which is most stable object? A C

B D

5 Diagram 3 shows a vase.

The stability of the vase can be improved byA reducing the volume of waterB adding two more stalks of rosesC putting the vase at a higher placeD adding some small stones into the vase

9.2 Importance of Stability

6 Which of the following can increase the stability of a sports car?

I Use wider tyresII Use larger tyresIII Increase the height of the car A I and II only C II and III onlyB I and III only D I, II and III

REVISION

1 Which of the following structure is more stable?I A retort standII An empty beakerIII A metre rule standing verticallyA I and II only C II and III onlyB I and III only D I, II and III

2 Which of the following statements is not true about stability?A A stable object does not topple easilyB Stability can be improved by increasing the base area of

the objectC An object with a smaller base area is more stable than

an object with a bigger base areaD The stability of an object depends on its base area and

the position of its centre of gravity

3 Diagram 1 shows two similar conical flasks arranged differently.

(a) Which of two arrangements, X and Y, is more stable? ___________________________________________

___________________________________________ (b) Explain your answer in (a).

____________________________________________ ____________________________________________