Waves - Shed Loads of Practice Questions

Calculating Period and Frequency

Remember, the formula for frequency (f) and period (T) are related as follows: f = 1/T, and T = 1/f.

Calculating Frequency from Period:

Q1

If a pendulum completes 20 oscillations in 10 seconds, what is the frequency of the pendulum's motion?

Q2

A guitar string vibrates with a period of 0.02 seconds. What is the frequency of the string's vibrations?

Q3

A sound wave completes 100 cycles in 2 seconds. Calculate the frequency of the sound wave.

Q4

An electronic signal has a period of 0.005 seconds. Determine the frequency of the signal.

Calculating Period from Frequency:

Q1

If the frequency of a radio wave is 100 MHz (megahertz), what is its period in seconds?

Q2

A light wave oscillates with a frequency of 5 × 10$^{14}$ Hz. What is the period of the light wave?

Q3

A vibrating tuning fork has a frequency of 440 Hz. Calculate the period of the tuning fork's vibrations.

Q4

An alternating current (AC) has a frequency of 60 Hz. Find the period of this AC signal.

Mixed Questions:

Q1

A wave has a period of 0.1 seconds. What is the frequency of the wave in Hertz?

Q2

If a signal oscillates with a frequency of 20 kHz, what is its period in milliseconds?

Q3

The vibrations of a guitar string have a frequency of 440 Hz. What is the period of the guitar string's vibrations in milliseconds?

Q4

An electronic device produces electromagnetic waves with a frequency of 2.4 GHz. Calculate the period of these waves in nanoseconds.

  • Calculating Frequency from Period:

    Q1

    2 Hz

    Q2

    50 Hz

    Q3

    50 Hz

    Q4

    200 Hz

    Calculating Period from Frequency:

    Q1

    $1 \times 10^{-8} $ s

    Q2

    $2 \times 10^{-15} $ s

    Q3

    $2.3 \times 10^{-3} $ s

    Q4

    0.017 s

    Mixed Questions:

    Q1

    10 Hz

    Q2

    $5 \times 10^{-5} $ s

    Q3

    $2.3 \times 10^{-3} $ s

    Q4

    $4.2 \times 10^{-10} $ s

Calculating Wavelength, Frequency, and Wave Speed

Remember, the wave speed (v) is related to wavelength (λ) and frequency (f) as follows: v = λ × f.

Calculating Wavelength:

Q1

A water wave travels with a speed of 2 m/s and has a frequency of 1 Hz. What is the wavelength of the water wave?

Q2

An electromagnetic wave has a frequency of 5 × 10^14 Hz and travels at the speed of light (3 × 10^8 m/s). Calculate the wavelength of this electromagnetic wave.

Q3

A sound wave with a frequency of 500 Hz travels at a speed of 340 m/s in air. Determine the wavelength of the sound wave.

Q4

A rope is oscillating with a frequency of 10 Hz, and a wave speed of 20 m/s. What is the wavelength of the wave on the rope?

Calculating Frequency:

Q1

A microwave oven emits radiation with a wavelength of 12.2 cm. What is the frequency of this microwave radiation?

Q2

A guitar string vibrates with a wavelength of 0.6 meters and travels at a speed of 120 m/s. Calculate the frequency of the guitar string's vibrations.

Q3

An ultrasound wave has a wavelength of 0.002 meters and travels at a speed of 1500 m/s. Find the frequency of this ultrasound wave.

Q4

A radio wave has a wavelength of 300 meters. What is the frequency of this radio wave in Hertz?

Calculating Wave Speed:

Q1

A light wave with a wavelength of 500 nm travels through a vacuum. Calculate the speed of this light wave.

Q2

A seismic wave has a wavelength of 20 meters and a frequency of 2 Hz. Determine the speed of this seismic wave.

Q3

An ocean wave with a wavelength of 10 meters travels at a speed of 5 m/s. What is the frequency of this ocean wave?

Q4

A rope wave has a wavelength of 0.4 meters and a frequency of 8 Hz. Calculate the speed of the wave on the rope.

Mixed Questions:

Q1

A sound wave travels through air with a speed of 340 m/s and has a wavelength of 0.68 meters. Calculate the frequency of this sound wave.

Q2

An electromagnetic wave has a frequency of 1.5 × 10$^9$ Hz and a wavelength of 0.2 meters. Determine the speed of this electromagnetic wave.

Q3

A water wave with a frequency of 2 Hz has a wavelength of 5 meters. What is the speed of this water wave?

  • Q1

    2 m

    Q2

    $6 \times 10^{-7} $ m

    Q3

    0.68 m

    Q4

    2m

    Calculating Frequency:

    Q1

    $2.5 \times 10^{9} $ Hz

    Q2

    200 Hz

    Q3

    $7.5 \times 10^{5} $ Hz

    Q4

    $1 \times 10^{6} $ Hz

    Calculating Wave Speed:

    Q1

    150 m/s

    Q2

    40 m/s

    Q3

    0.5 Hz

    Q4

    3.2 m/s

    Mixed Questions:

    Q1

    500 Hz

    Q2

    $3 \times 10^{8} $ m/s

    Q3

    10 m/s

Calculating Distance from Radar or Sound Echo

Remember to use the formula: distance = (speed) × (time) for both radar and sound echo calculations.

Using Radar (Speed of Light):

Q1

A radar signal is emitted and returns after 0.02 seconds. Assuming the speed of light is 3 × 10^8 m/s, calculate the distance to the object the radar signal bounced off.

Q2

An aircraft is detected by a radar system 10 kilometres away. If the radar signal took 0.033 seconds to return, what is the speed of the radar signal?

Q3

A radar signal takes 1.5 microseconds to travel to a satellite and back. Calculate the distance from the radar station to the satellite, assuming the speed of light is $3 \times 10^{8} $ m/s.

Using Sound Echo (Speed of Sound):

Q1

A bat emits a sound wave, and it returns as an echo after 0.1 seconds. Assuming the speed of sound in air is 343 m/s, how far away is the object the sound wave bounced off?

Q2

In a canyon, a yell is echoed back after 2 seconds. If the speed of sound in air is 340 m/s, calculate the distance to the canyon wall.

Q3

A submarine sends out a sonar signal, and the echo returns in 0.12 seconds. If the speed of sound in water is 1500 m/s, find the distance to the underwater object.

Mixed Questions:

Q1

A radar system detects a mountain at a distance of 20 kilometres. The radar signal took 0.067 seconds to return. Determine the speed of the radar signal.

Q2

A sound wave is produced underwater and returns as an echo after 1.5 seconds. If the speed of sound in water is 1482 m/s, calculate the distance to the underwater object.

Q3

A meteorological radar detects rain clouds 15 km away. The radar signal took 0.05 seconds to return. Find the speed of the radar signal.

Q4

A sound wave is emitted and returns as an echo after 0.4 seconds. If the speed of sound in air is 343 m/s, determine the distance to the reflecting surface.

Q5

A submarine's sonar signal returns in 0.08 seconds after being emitted. Assuming the speed of sound in water is 1500 m/s, calculate the distance to the underwater object.

Q6

A radar signal takes 0.007 seconds to travel to an aircraft and back. If the speed of light is 300,000,000 m/s, calculate the distance from the radar station to the aircraft.

  • Using Radar (Speed of Light):

    Q1

    $3 \times 10^{6} $ m

    Q2

    $6.1 \times 10^{5} $ m/s

    Q3

    225 m

    Using Sound Echo (Speed of Sound):

    Q1

    17.2 m

    Q2

    340 m

    Q3

    90 m

    Mixed Questions:

    Q1

    $6 \times 10^{5} $ m/s

    Q2

    1112 m

    Q3

    $6 \times 10^{5} $ m/s

    Q4

    68.6 m

    Q5

    60 m

    Q6

    $1.05 \times 10^{6} $ m

Calculating Lens Magnification

Remember, magnification (M) is calculated using the formula: M = (image height / object height) = (image distance / object distance).

Question 1:

A convex lens has an object placed 20 cm in front of it. The image formed is 5 cm tall. Calculate the magnification of the lens.

Question 2:

An object is placed 30 cm in front of a concave lens. The image formed is 10 cm tall. Calculate the magnification of the lens.

Question 3:

A magnifying glass produces an image of an object that is 3 times larger than the object itself. If the object is 2 cm tall, calculate the image height.

Question 4:

A convex lens produces an image that is 2 times larger than the object. If the image is 8 cm tall, calculate the height of the object.

Question 5:

A concave lens forms an image that is 1.5 times taller than the object. If the object is 10 cm tall, calculate the image height.

Question 6:

An object is placed 25 cm in front of a convex lens. The image formed is 3 cm tall. Calculate the magnification of the lens.

Question 7:

A magnifying glass produces an image that is 4 times larger than the object. If the object is 1.5 cm tall, calculate the image height.

Question 8:

A concave lens produces an image that is 0.8 times the size of the object. If the image is 6 cm tall, calculate the height of the object.

Question 9:

An object is placed 40 cm in front of a convex lens. The image formed is 4 cm tall. Calculate the magnification of the lens.

Question 10:

A convex lens forms an image that is 1.2 times taller than the object. If the object is 15 cm tall, calculate the image height.

Question 11:

A magnifying glass produces an image that is twice the size of the object. If the image is 5 cm tall, calculate the height of the object.

Question 12:

A concave lens produces an image that is 0.6 times the size of the object. If the object is 8 cm tall, calculate the image height.

  • Answer 1:

    Magnification = Image Height / Object Height Magnification = 5 cm / 20 cm = 0.25

    Answer 2:

    Magnification = Image Height / Object Height Magnification = 10 cm / 30 cm = 0.33

    Answer 3:

    Image Height = Magnification * Object Height Image Height = 3 * 2 cm = 6 cm

    Answer 4:

    Object Height = Image Height / Magnification Object Height = 8 cm / 2 = 4 cm

    Answer 5:

    Image Height = Magnification * Object Height Image Height = 1.5 * 10 cm = 15 cm

    Answer 6:

    Magnification = Image Height / Object Height Magnification = 3 cm / 25 cm = 0.12

    Answer 7:

    Image Height = Magnification * Object Height Image Height = 4 * 1.5 cm = 6 cm

    Answer 8:

    Object Height = Image Height / Magnification Object Height = 6 cm / 0.8 = 7.5 cm

    Answer 9:

    Magnification = Image Height / Object Height Magnification = 4 cm / 40 cm = 0.1

    Answer 10:

    Image Height = Magnification * Object Height Image Height = 1.2 * 15 cm = 18 cm

    Answer 11:

    Object Height = Image Height / Magnification Object Height = 5 cm / 2 = 2.5 cm

    Answer 12:

    Image Height = Magnification * Object Height Image Height = 0.6 * 8 cm = 4.8 cm