Page 140 - Physics

Physics for Secondary Schools

limit of proportionality. What is the (b) The gravitational fi eld strength
new extension of the spring? on planet X is equal to the

(a) 6.0 cm (c) 36 cm gravitational fi eld strength on
(b) 24 cm (d) 48 cm planet Y.
(c) The gravitational fi eld strength
(v) If the radius of a capillary tube is on planet X is one-third of the
reduced while keeping all other gravitational fi eld strength on
factors constant, how will it affect planet Y.
the capillary rise height? (d) The gravitational fi eld strength
(a) The capillary rise will increase. on planet X is three times the

(b) The capillary rise will decrease. gravitational fi eld strength on
(c) The capillary rise will remain planet Y.
the same.
(d) The capillary rise will become Section B
unpredictable. 2. (a) State Hooke’s law and express
it in mathematical form.
(vi) The graph in Figure 6.18 shows how (b) An object with a mass of 500
the extension of a spring changes g was hung from the spring with
with the masses suspended from it a force constant of 20 N/m.
when the spring is on planet X and (i) How far in centimetres
when the spring is on planet Y. would the spring stretch?
(ii) What is the mass of an
object that stretches the
Planet X spring 35 cm long? (take
50
g = 0.01 N/g).
Extension (cm) 30 Planet Y 3. (a) Explain why water wets glass
40
while mercury does not.
(b) Explain how the knowledge of
20
adhesion and cohesion is useful
in daily life.
10
4. (a) Explain why mosquitoes can
0 1 2 3 4 5 6 manage to walk on the surface
Mass (kg) of water.
Figure 6.18 (b) Explain why when washing
clothes, we use a soap/detergent.
Which conclusion can be drawn from 5. (a) Differentiate between capillarity
these graphs? and surface tension.
(a) It is not possible to compare the (b) Which phenomenon is taking
gravitational fi eld strengths on place when kerosene rises up a
planets X and Y. wick?

134
Student’s Book Form One

Physics Form 1 Final.indd 134 16/10/2024 20:57