Page 75 - Physics Form 5 KSSM_Neat

Example 2 CHAPTER 2

A technician intends to design a hydraulic brake Output Pressure
system for his bicycle as shown in Photograph 2.6. cylinder
The input force that a cyclist is able to exert
is 60 N at the input cylinder which has a
cross-sectional area of 0.80 cm . What is the
2
cross-sectional area of the output cylinder
that will produce a braking force of 840 N? Input
cylinder
Solution

Input force, F = 60 N
1 Photograph 2.6
Cross-sectional area of input cylinder, A = 0.80 cm 2
1
Output force (braking force), F = 840 N
2
Cross-sectional area of output cylinder = A 2
F F
Formula for Pascal’s principle, 2 = 1
A 2 A 1
840 60
=
A 0.80
2
A = 840 × 0.80
2 60
KEMENTERIAN PENDIDIKAN MALAYSIA
= 11.2 cm
2

Formative Practice 2.4

1. State Pascal's principle.
2. Describe how a hydraulic machine can achieve force multiplication by applying
Pascal's principle.

3. In a hydraulic system, an input force of 4.0 N acts on a piston with surface area 0.50 cm .
2
2
Calculate the output force produced on a piston with surface area 6.4 cm .
4. A pupil has a small syringe with a piston of diameter 1.5 cm. The pupil intends to
construct a hydraulic system that can multiply force from 6 N to 72 N. What is the
diameter of a large syringe that is required for this hydraulic system?

LS 2.4.4 65