Question
A car moves at a speed of 36 km h^{–1} on a level road. The coefficient of friction between the tyres and the road is 0.8. The car negotiates a curve of radius R. If g = 10 ms^{ –2}, the car will skid (or slip) while negotiating the curve if value of R^{ }is ^{ }

10 m & 12.5 m

12 m

14 m

16 m
easy
Solution
10 m & 12.5 m
Speed of car (v) = 36 kmh^{–1} = 10 ms^{–1}. The maximum centripetal force that friction can provide is
this is the minimum radius the curve must have for the car to negotiate it without sliding at a speed of 10 ms^{ –1}.
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