- #1
bartieshaw
- 50
- 0
i have been set the following question
theta = 3r^2
find the magnitude of the acceleration when
r=0.8 m
dr/dt = 4ms^-1
d^2r/dt^2 = 12 ms^-2
my working followed the process of calculating angular velocity with these conditions and angular acceleration with these conditions then plugging them into the acceleration formula for a polar coordinate system.
when doing this i get
a(radial) = -282.912 ms^-2 (componant along the radius)
a(theta) = 218.88 ms^-2 (componant perpendicular to radius)
using pythagoras to calculate the magnitude of the resultant acceleration i get a value 357.7 ms^-2
a value my dynamics lecturer is prompt to tell me is WRONG. perhaps someone can help me...PLEASE
theta = 3r^2
find the magnitude of the acceleration when
r=0.8 m
dr/dt = 4ms^-1
d^2r/dt^2 = 12 ms^-2
my working followed the process of calculating angular velocity with these conditions and angular acceleration with these conditions then plugging them into the acceleration formula for a polar coordinate system.
when doing this i get
a(radial) = -282.912 ms^-2 (componant along the radius)
a(theta) = 218.88 ms^-2 (componant perpendicular to radius)
using pythagoras to calculate the magnitude of the resultant acceleration i get a value 357.7 ms^-2
a value my dynamics lecturer is prompt to tell me is WRONG. perhaps someone can help me...PLEASE