A sound wave produces a maximum pressure increase on a mammal's eardrum of 4.5×10−3 N m−24.5 \times 10^{-3}\text{ N m}^{-2}4.5×10−3 N m−2. This pressure wave is transmitted to the fluid of the inner ear, where the maximum pressure increase is measured to be 1.2×10−1 N m−21.2 \times 10^{-1}\text{ N m}^{-2}1.2×10−1 N m−2.
Explain how the ossicles in the middle ear contribute to increasing the pressure transmitted to the inner ear fluid.
The mammal's tympanic membrane (eardrum) can be assumed to be circular with a diameter of 0.90 cm0.90\text{ cm}0.90 cm. Assuming that the lever action of the ossicles multiplies the force transmitted to the oval window by a factor of 1.4, calculate the surface area, in m2\text{m}^2m2, of the oval window.
14 exam-style questions on AQA A Level Physics Physics of the ear (A-level only), covering Ear as a sound detection system (A-level only), Sensitivity and frequency response (A-level only), and Defects of hearing (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.