Determining Period - if the object is moving/vibrating slowly you could measure each period with a stopwatch - if it is going faster we can use the formula below T = Δt T - period (seconds) Δt N - time interval (seconds) N - number of cycles (no units) Example W.1 Through experimentation it is determined that the pendulum makes 40 cycles in 25 seconds. Determine the period. Example W.2 A spring is bouncing up and down. If it takes 0.40 seconds to complete one cycle, how many cycles would be completed in 2 minutes. Determining Frequency -frequency is the number of cycles completed in a given time interval (usually in one second) - it is the inverse of the period = N frequency ( /s or Hz) f f = Δt N = number of cycles (no unit) Δt = time interval (s) OR 1 frequency ( /s or Hz) f = f = T T = period (sec) Example W.3 A blade on a lawnmower makes 4000 revolutions in 1 minute. Determine a) frequency b) period Wave Behavior A is a disturbance that transfers energy through a medium. wave The speed of the wave in a medium is a property of the medium. For example: sound waves move faster in water than they do through air. However, not all waves require a medium and as such waves can be broken down into 2 main categories. Two types of waves 1. - require a medium such water waves, sound waves, mechanical waves in strings, slinkies, etc 2. - do not require a medium, they can travel through a vacuum such as electromagnetic you would encounter in space - examples would be light waves, radio and TV waves and microwaves
Determining Period - if the object is moving/vibrating slowly you could measure each period with a stopwatch - if it is going faster we can use the formula below T = Δt T - period (seconds) N Δt - time interval (seconds) N - number of cycles (no units) Example W.1 Through experimentation it is determined that the pendulum makes 40 cycles in 25 seconds. Determine the period. Example W.2 A spring is bouncing up and down. If it takes 0.40 seconds to complete one cycle, how many cycles would be completed in 2 minutes. Determining Frequency -frequency is the number of cycles completed in a given time interval (usually in one second) - it is the inverse of the period f = N f = frequency ( /s or Hz) Δt N = number of cycles (no unit) Δt = time interval (s) OR f = 1 f = frequency ( /s or Hz) T T = period (sec) Example W.3 A blade on a lawnmower makes 4000 revolutions in 1 minute. Determine a) frequency b) period Wave Behavior A wave is a disturbance that transfers energy through a medium. The speed of the wave in a medium is a property of the medium. For example: sound waves move faster in water than they do through air. However, not all waves require a medium and as such waves can be broken down into 2 main categories. Two types of waves 1. mechanical - require a medium such water waves, sound waves, waves in strings, slinkies, etc 2. electromagnetic - do not require a medium, they can travel through a vacuum such as you would encounter in space - examples would be light waves, radio and TV waves and microwaves
Waves%202013.docx