Unit 4: Simple harmonic motion Flashcards
Describe one full cycle of motion
From maximum height at one side to maximum height on the other side and then back again
What is the lowest point of a swing referred to as?
The equilibrium position as this is where it will come to a standstill
Describe the motion of an oscillating object
An oscillating object moves repeatedly one way then in the opposite direction through its equilibrium position
What is displacement in terms of the equilibrium position?
The distance and direction from the equilibrium position
What is the amplitude of oscillations?
The maximum displacement of the oscillating object from equilibrium
What are features of free oscillations?
The amplitude is constant and there are no frictional forces
What is the time period?
The time for one complete cycle of oscillations
What is frequency and what is its unit?
The number of cycles per second and its unit is the hertz
What is the formula that relates time period and frequency?
T = 1/f
What is the formula for angular velocity in terms of the time period?
ω = 2π/T
What is the unit of angular velocity?
Radians per second
How can you tell if two objects are oscillating out of phase?
One object will reach maximum displacement on one side at a certain time, Δt, later than the other object
What is the formula for the phase difference in radians when two objects are oscillating at the same frequency and how is it different if you want the phase difference in degrees?
2πΔt/T in radians and 360Δt/T in degrees where Δt is the time between successive instants when the two objects are at maximum displacement in the same direction
Does the phase difference of two objects oscillating stay the same?
Yes
When do two objects oscillate in phase?
If Δt = T
What is a phase difference of 2π equal to?
0
How does the velocity of an oscillating object change in terms of the equilibrium?
An oscillating object speeds up as it returns to equilibrium and it slows down as it moves away from equilibrium
When will the amplitude of the oscillations be constant?
Provided friction is negligible
What does the gradient of a displacement-time graph represent?
Velocity
What does the gradient of a velocity-time graph represent?
Acceleration
When is the velocity of an object greatest?
When the gradient of the displacement-time graph is greatest i.e. when the object passes through equilibrium
When is the velocity zero?
When the gradient of the displacement-time graph is zero i.e. at maximum displacement
When is the acceleration greatest?
When the gradient of the velocity-time graph is greatest, this occurs when the velocity is zero and occurs at maximum displacement in the opposite direction
When is the acceleration zero?
When the gradient of the velocity-time graph is zero (the speed is at a maximum), this is when the displacement is zero