Exams › NEET › Physics

A car of mass \(m\) is moving on a level circular track of radius \(R\). If \(\mu_s\) represents the static friction between the road and the tyres of the car, the maximum speed of the car in circular motion is given by:

1. \(\mu_s \sqrt{Rg}\)
2. \(\sqrt{Rg/\mu_s}\)
3. \(\mu_s \sqrt{Rg/m}\)
4. \(\sqrt{Rg\mu_s}\)

Correct answer: \(\mu_s \sqrt{Rg}\)

Solution

The maximum centripetal force on a level road is provided by static friction, \(\mu_s mg\). Equating this to \(mv^2/R\) gives \(v_{\max} = \sqrt{\mu_s g R}\).

Related NEET Physics questions

• A stone tied to a string of length 80 cm is whirled in a horizontal circle at constant speed, completing 14 revolutions in 25 s. What is the magnitude of the centripetal acceleration of the stone?
• A coin on a rotating turntable begins to slip when placed 4 cm from the center. If the turntable's angular speed is doubled, at what distance from the center will the coin just start to slip?
• The angular displacement of a rotating body is described by $\theta(t) = \omega_0 t + \frac{1}{2}\alpha t^2$, where $\omega_0 = 1\ \text{rad/s}$ and $\alpha = 1.5\ \text{rad/s}^2$. What is the angular velocity of the body at $t = 2\ \text{s}$?
• A coin rests on a gramophone record rotating at angular velocity \(\omega\). The coefficient of static friction is \(\mu\). The coin rotates without slipping if its distance \(r\) from the center satisfies:
• Two racing cars of masses \(m_1\) and \(m_2\) travel in circles of radii \(r_1\) and \(r_2\), respectively. Both complete one full revolution in the same time period \(t\). What is the ratio of the angular speed of the first car to the second car?
• A wheel starts from rest and undergoes uniform angular acceleration, reaching an angular velocity of 80 rad/s after 5 seconds. What is the total angular displacement of the wheel during this time?

⚔️ Practice NEET Physics free + battle 1v1 →