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con31773
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A subway train rounds an unbanked curve at 67km/h. A passenger, hanging onto a strap notices an adjacent strap is unused and makes an angle of 15° to the vertical. What is the radius of the turn?
Relation of sines, opposite and hypotenuse of a right triangle. Opposite length=Hypotenuse*sin(angle)
circular motion equations, such as f=mv[itex]^{2}[/itex]/r
First convert the speed into meters per second. 67000m/h=18.61m/s
I recognised that the force causing the angle is centrifugal force, and will be equal in magnitude to the centripetal force. Centrifugal force=mgsin(15)=mv[itex]^{2}[/itex]/r (from soccahtoa)
r=v[itex]^{2}[/itex]/gsin(15) plug in
r=136.4m, which of course is incorrect.
Any help would be greatly appreciated.
Relation of sines, opposite and hypotenuse of a right triangle. Opposite length=Hypotenuse*sin(angle)
circular motion equations, such as f=mv[itex]^{2}[/itex]/r
First convert the speed into meters per second. 67000m/h=18.61m/s
I recognised that the force causing the angle is centrifugal force, and will be equal in magnitude to the centripetal force. Centrifugal force=mgsin(15)=mv[itex]^{2}[/itex]/r (from soccahtoa)
r=v[itex]^{2}[/itex]/gsin(15) plug in
r=136.4m, which of course is incorrect.
Any help would be greatly appreciated.