Question

Can anybody explain this ???​

Answer 1

10% margin implies that, an increase or decrease in speed from minimum velocity by about 10% can still be considered as safe speed. Therefore, even though the actual safe speed for banking is v(min), an increase or decrease in speed up to 10%  can be used to bank the road. This means that the minimum speed that vehicle can obtain to safely bank the curve will be ( v + 10%v) and maximum speed to bank the road will be (v - 10%v) which is the speed limit.

i.e. 10% margin means the actual speeds obtained must differ from the obtained speed by a sum or difference of 10% of obtained speed.

Obtained value for min speed is 5.196m/s

Therefore, speed limit or maximum speed with which the vehicle can bank safely is 5.196 + 10% 5.196

Similarly, Minimum speed obtained will be 8.775 - 10%8.775 = 7.896 m/s