The figure below shows a car braking system. The brake fluid is an oily liquid. The brake drum rotates with the wheel of the car. (i) Explain...

The figure below shows a car braking system. The brake fluid is an oily liquid.

The brake drum rotates with the wheel of the car.
(i) Explain how pushing the brake pedal makes the brake rub against the drum.
(ii) The cross-sectional area of the master piston is 2.0cm². A force of 140N is applied to the master piston.
(I) Calculate the pressure created in the brake fluid by the master piston.
(II) The cross-sectional area of each slave piston is 2.8cm². Calculate the force exerted on each slave piston by the brake fluid.
(III) The force exerted on the master piston is greater than the force applied by the foot on the brake pedal. Using the principle of moments, explain this

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(i) When the pedal is pushed, pressure is generated in the master cylinder; This pressure is
transmitted to the slave cylinder; This causes the pistons of the slave cylinder to open the brake shoe and hence the brake lining presses the drum.

(III) Distance from the foot to pivot is larger than piston to pivot;
Force x distance = Constant

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Kavungya answered the question on May 31, 2019 at 05:32

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