Question

Solve this class 9 physics icse​

Answer 1

Given :

• Area of cross section of Piston A = 8 cm²

• Area of cross section of Piston B = 320 cm²

• Mass = 4 kg

To Find :

• Pressure on Piston A

• Pressure of Piston B

• Thrust on Piston B

Solution :

i) To find the pressure, first of all we'll have to find the Thrust that is the effort applied and it is given to be of 4 kg

$\bigstar \: \sf \: Pressure = \dfrac{Thrust}{Area}$

$\longrightarrow \: \sf \: Pressure _A= \dfrac{4}{8}$

$\longrightarrow \: \red{ \sf \: Pressure _A= 0.5 \: kgf \: {cm}^{ - 2} }$

ii) According to Pascal's law :

Pressure acting on A = Pressure acting on B

$\longrightarrow \red{ \sf \: Pressure _B= 0.5 \: kgf \: {cm}^{ - 2} }$

iii) We know that, Pressure = Thrust/Area. So,

$\bigstar \: \sf \: Thrust = Pressure \times Area$

$\longrightarrow \sf Thrust = \:4\times \dfrac{320}{8}$

$\longrightarrow \sf \:Thrust = 4\times 40$

$\longrightarrow \red{ \sf \:Thrust = 160 \: kgf \:}$

Answer 2

Answer:

Hey mate here is your answer

Given,

Area of piston A = 8cm^2

Area of piston B = 320cm^2

Mass = 4kg

To find:-

(i) The pressure on Piston A

Pressure acting on Piston A in the downward direction = Thrust / Area

= 4kg / 8cm^2

= 0.5kg.cm^2

Pressure acting on Piston A = 0.5kg.cm^2

(ii) The pressure on Piston B

According to Pascal law,

Pressure acting on Piston A = Pressure acting on Piston B.

So, Pressure on Piston B is 0.5kg.cm^2.

(iii) Thrust on Piston B

Thrust acting on Piston B in upward direction = Pressure × Area of Piston B

= 0.5 × 320 = 160kg.