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A car of mass m = 1000 kg is moving with constant speed v = 10 m/s on a parabolic shaped bridge AFOE of span l=40m and height h = 20 m as shown in the figure. Then the net force applied by the bridge on the car when the car is at point F, is |
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Answer» `5000 sqrt((5)/(2))N`  So, slope at `F=(dy)/(dx)=(2x)/(20)=(2xx10)/(20)=1` At point F, `mg=(1)/(sqrt(2))-N=(mv^(2))/(R)` `N=(mg)/(sqrt(2))-(mv^(2))/(R) and f_(s)=(mg)/(sqrt(2))` At F, `R=((1+1)^(3//2))/((1)/(10)) = 20 sqrt(2)` (metre) `N=(10m)/(sqrt(2))-(100m)/(20sqrt(2))=(5m)/(sqrt(2))` `f_(s)=(20m)/(sqrt(2))` `because ` Net force `=m sqrt((25)/(2)+(100)/(2))=5m sqrt((5)/(2))N` |
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