912.
outer ear:
pinna
ear canal
middle ear:
ossicles and ear drum
inner ear:
semcircular canals
cochlea
auditory nerve
13.
frequency = wavespeed ÷ wavelength
14.
if frequency increases you would experience a higher pitch in sound
15.
humans can hear 20Hz to 20kHz
16.
The Doppler effect is the change in frequency or wavelength of a wave for an observer who is moving relative to the wave source. Can be used for machines measuring speed via doppler effect.
17.
Doppler in hospitals can be used for ultrasound to provide images for diagnosis and monitoring.
Answer:
Explanation:
By Ohms Law, Voltage = Current * Resistance
Keeping the voltage the same and doubling the resistance, the current will be halved.
So the new current = 1.5/2 = 0.75A
Answer:

Explanation:
We could use conversation of energy. Total distance the stone will cover will be

the Final velocity will be

Answer:
Therefore it is save to carry a 62kg adult
Explanation:
From the question we are told that:
Mass 
Height of supporting Rock 
Length of Board
Mass of board 
Mass of adult
Generally the moment of balance about wedge part about is mathematically given by



where

therefore

if N=0 at fallen person

Therefore it is save to carry a 62kg adult