Flashcards
Circular Motion
Flashcards do conjunto (16)
- 1What is the angle in radians equal to in a circle?The arc length divided by the radius.
- 2Why are there 2π radians in a circle?The arc length is the circumference so 2πr and the radius is r. So there are 2πr/r = 2π radians.
- 3How do you convert from degrees to radians?Angle in radians = angle in degrees x π/180.
- 4What do the following symbols stand for in the circular motion equations and what are there units? ω, θ, t, r, f, T, a, F.ω = angular speed in rads^-1
θ = ange that the object turns through, rad
t = time, s
r = radius of circle of rotation, m
f = frequency, revs^-1 or Hz
T = period, s
a = centripetal acceleration, ms^-2
F = centripetal force, N - 5What is angular speed?The angle through which a point on a rotating object rotates each second.
- 6What is the equation for angular speed? What are the units for each component?ω = θ/t
ω = angular speed ( rads^-1),
θ = angle that the object turns through (rad)
t = time (s) - 7How can the angular speed be written in terms of the linear speed?Consider an object moving in a circular path of radius r that moves θ radians in t seconds. Linear speed is the distance/time.
v = arc length/t
Know that arc length = rθ
so v = rθ/t
v/r = θ/t
Know that ω = θ/t
so ω = v/r - 8What is frequency in circular motion? What are the units?The number of complete revolutions per second. revs^-1
- 9What is the equation for frequency for circular motion?f = 1/T
- 10For circular motion how do you get to the equation ω = 2πf?For a complete circle, an object turns through 2π radians in a time T,
so ω = 2π/T.
Replace 1/T with f.
ω = 2πf. - 11Are objects in circular motion accelerating and why is this?Yes because their velocity is changing this is because even if its speed is constant its direction is changing.
- 12What is the acceleration called in circular motion? Where is it always directed?Centripetal acceleration. Towards the centre of the circle.
- 13What is the symbol for centripetal acceleration? What are the units for centripetal acceleration?a, ms^-2
- 14Why must an object travelling in a circle have a force acting on it?Because Newton's first law of motion says that an object's velocity will stay the same unless there's a force acting on it. An object travelling in a circle has a centripetal acceleration so there must be a force causing this acceleration.
- 15What is centripetal force?The force on an object moving with circular motion. It's directed towards the centre of the circle, and is responsible for the objects curved path?
- 16What would happen if the centripetal force on an object moving in a circle was removed?The object would fly of at a tangent with velocity v.
Informações
- Descrição
- A2 Physics (A2 Further Mechanics) FlashCards sobre Circular Motion, criado por Jasmine Bayliss-Dagg em 19-10-2017.
- Criado por
- Jasmine Bayliss-Dagg
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