Laws of Motion - Result Question 59

«««< HEAD:content/english/neet-pyq-chapterwise/physics/laws-of-motion/laws-of-motion-result-question-59.md

59. A car of mass $1000 kg$ negotiates a banked curve of radius $90 m$ on a frictionless road. If the banking angle is $45^{\circ}$, the speed of the car is :

======= ####59. A car of mass $1000 kg$ negotiates a banked curve of radius $90 m$ on a frictionless road. If the banking angle is $45^{\circ}$, the speed of the car is :

3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed:content/english/neet-pyq-chapterwise/physics/laws-of-motion/laws-of-motion—result-question-59.md (a) $20 ms^{-1}$

(b) $30 ms^{-1}$

(c) $5 ms^{-1}$

(d) $10 ms^{-1}$

[2012]

Show Answer

Answer:

Correct Answer: 59. (c)

Solution:

  1. (c) For banking, $\tan \theta=\frac{V^{2}}{R g}$

$\tan 45^{\circ}=\frac{V^{2}}{90 \times 10}=1$

$V=30 m / s$

If friction is present then maximum safe speed, on

a banked frictional road, $V=\sqrt{\frac{R g(\mu+\tan \theta)}{1-\mu \tan \theta}}$