Kinematics Question 471
Question: Assertion: As the frictional force increases, the safe velocity limit for taking a turn on an unbanked road also increases. Reason: Banking of roads will increase the value of limiting velocity.
Options:
A) If both assertion and reason are true and the reason is the correct explanation of the assertion.
B) If both assertion and reason are true but reason is not the correct explanation of the assertion.
C) If assertion is true but reason is false.
D) If the assertion and reason both are false.
E) If assertion is false but reason is true.
Show Answer
Answer:
Correct Answer: B
Solution:
On an unbanked road, friction provides the necessary centripetal force $ \frac{mv^{2}}{r}=\mu mg $
$ \therefore v=\sqrt{\mu rg}. $
Thus with increase in friction, safe velocity limit also increases.
When the road is banked with angle of q then it’s limiting velocity is given by $ v=\sqrt{\frac{rg(\tan \theta +\mu )}{1-\mu \tan \theta }} $ .
Thus limiting velocity increase with banking of road.
