Question

PLEASE HELP!

Answer 1

1. Answer;

All of the above

A mechanical wave;

• Carries energy from one place to another
• Moves through solids, liquids, and gasses
• Is created when a source of energy creates a vibration

Explanation;

• A wave is a transmission of a disturbance from one place to another. It involves transmission of energy from the source to other points.
• Waves may or may not require a material medium for transmission. Those waves that do not require a material medium for transmission are called electromagnetic waves while those that require a material medium for transmission are the mechanical waves.
• Mechanical waves include sound waves which travel through various types of matter, solids, liquids and gases. The transmission of waves is through vibration of particles in the medium of transmission and therefore energy is transferred from one point to another through the medium.

2. Answer;

A longitudinal wave

Explanation;

• Mechanical waves are types of waves that require a material medium for transmission. An example of mechanical wave is the sound wave whose transmission occurs in medium such as solids, liquids and gases.
• The transmission of mechanical waves involves vibration of particles through the medium of transmission, thus transfer of energy from one point to another. The vibration of particle may be in the form of a longitudinal wave or a transverse wave.
• In a longitudinal wave the vibration of particles is parallel to the direction of the wave motion while in a transverse wave the vibration of particles is perpendicular to the direction of the wave motion.

3. Answer;

100 mm/s

Explanation and solution;

• Frequency of a wave refers to the number of complete oscillation in one second, while wavelength refers to the distance between two successive crests or troughs in a transverse wave or between two rarefactions or compression in a longitudinal wave.

• The speed of a wave or the velocity is directly influenced by the wavelength and the frequency of the wave.

• The speed of a wave is given by the product of frequency and wavelength.

Speed = frequency × wavelength

           = 20 × 5

            = 100 mm/s

4. Answer;

The maximum displacement from the rest position

Explanation;

• Amplitude of a wave refers to the maximum displacement of particles on a given medium from the rest position in a wave. E.g from the rest position to the crest in a transverse wave.  Amplitude shows a how big the oscillation in a wave are.
• Amplitude is an important aspect of a wave as it determines the amount of energy carried by a wave, such that a high energy of a wave is characterized by high amplitude while low energy relates to a low amplitude.

5. Answer;

Changes speed

Explanation;

• Refraction of a wave is one of the property of waves that occurs when a wave changes direction when it passes from one medium to another. This occurs as a result of bending of the wave which occurs since the mediums involved are of different density and refractive index.
• Example of refraction is the bending of light wave or a sound wave, or the bending of lights that occurs when the light enters the eye to form the image that one sees, this is because of the lens in the eye.
• Apart from the change in direction, refraction is always results to the change in wavelength and speed of the wave.

6. Answer;

Amplify the sound

Explanation;

• Sound is a example of mechanical waves that require material medium for transmission. Sound travels through solids, liquids and gases at different velocities.
• Transmission of sound waves is as a result of vibration of particles, thus the transfer of energy from one point to another.
• Sound travels faster in solids as the particles are more closely packed thus there are more vibrations which means the transmission will be faster. Thus, the use of a resonance wooden sound board which is solid amplifies the sound wave by aiding faster transmission.

7. Answer;

Higher than when the source is stationary

Explanation;

• When a sound source approaches you, the pitch you hear is higher than when the source is stationary.

• Sound is a example of mechanical waves that require material medium for transmission.Transmission of sound waves is as a result of vibration of particles, thus the transfer of energy from one point to another.
• The pitch of the sound would increase when the sound source approaches  you because the vibration of particles will increased as the distance traveled by the wave decreases.

8. Answer;

The inner ear

Explanation;

• The inner ear is the part of the ear that send coded nerve signals to the brain for interpretation.
• The inner ear is the part of the ear which is inner most. It comprises of various parts which includes, cochlea, the vestibular, the balance mechanisms and the auditory nerve.
• The auditory nerve, part of the inner ear is responsible for carrying of the information between the inner ear and the brain. It transmits nerve signals or what we call coded nerve signals from the inner ear to the brain, where these electrical signals are translated to sound which we can listen to and understand.

Answer 2

1. All of the above 2. A longitudinal wave 3. 100 mm/s 4. the maximum displacement from the rest position 5. changes speed 6. amplify the sound 7. higher than when the source is stationary 8. the inner ear