Test Index

Motion in a Plane

© examsnet.com
Question : 18 of 32
Marks: +1, -0
An aircraft executes a horizontal loop of radius 1.00 km with a steady speed of 900 km h−1^{-1}. Compare its centripetal acceleration with the acceleration due to gravity.
Solution:  
Here, r=1 km=1000 m;r = 1\,\text{km} = 1000\,\text{m};
v=900 km h−1=900×10003600 m s−1v = 900\,\text{km}\,\text{h}^{-1} = 900 \times \frac{1000}{3600}\,\text{m}\,\text{s}^{-1} =250 m s−1= 250\,\text{m}\,\text{s}^{-1}
The centripetal acceleration of the aircraft is given by
a=v2r=(250)21000a = \frac{v^{2}}{r} = \frac{(250)^{2}}{1000} =625001000=62.5 m s−2= \frac{62500}{1000} = 62.5\,\text{m}\,\text{s}^{-2}
Acceleration due to gravity, g=9.8 m s−2g = 9.8\,\text{m}\,\text{s}^{-2}
∴Centripetal accelerationAcceleration due to gravity=ag=62.59.8\therefore \frac{\text{Centripetal acceleration}}{\text{Acceleration due to gravity}} = \frac{a}{g} = \frac{62.5}{9.8} or ag=6.4\frac{a}{g} = 6.4 or a=6.4ga = 6.4 g
© examsnet.com
Go to Question: