$Assertion$ : There is a stage when frictional force is not needed at all to provide the necessary centripetal force on a banked road.
$Reason$ : On a banked road, due to its inclination the vehicle tends to remain inwards without any chances of skidding.
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
If the Assertion is correct but Reason is incorrect.
If both the Assertion and Reason are incorrect.
A motorcycle is going on an overbridge of radius $R$. The driver maintains a constant speed. As the motorcycle is ascending on the overbridge, the normal force on it
$A$ particle is moving in a circle :
You may have seen in a circus a motorcyclist driving in verttical loops inside a 'deathwell (a hollow spherical chamber with holes, so the spectators can watch from outside). Explatn clearly why the motorcyclist does not drop down when he is at the uppermost potnt, with no support from below. What is the minimum speed required at the uppermost position to perform a vertical loop if the radius of the chamber is $25 \;m ?$
$Assertion$ : Mountain roads rarely go straight up the slope.
$Reason$ : Slope of mountains are large, therefore more chances of vehicle to slip from roads
A car turns a corner on a slippery road at a constant speed of $10\,m/s$. If the coefficient of friction is $0.5$, the minimum radius of the arc in meter in which the car turns is