What is the maximum acceleration of a train such that a $50 \ kg$ box lying on its floor remains stationary (in $m \ s^{-2}$)? (Given: Coefficient of static friction between the box and the train's floor is $0.3$ and $g = 10 \ m \ s^{-2}$)

The limiting friction between two bodies in contact is independent of

Calculate the maximum acceleration (in $m s^{-2}$) of a moving car so that a body lying on the floor of the car remains stationary. The coefficient of static friction between the body and the floor is $0.15$ $(g = 10 m s^{-2})$.

Impending relative motion is opposed by which type of friction?

$A$ block of mass $M$ is placed on a horizontal surface and it is tied with an inextensible string to a block of mass $m$,as shown in the figure. $A$ block of mass $m_0$ is also placed on $M$. If $\mu$ is the coefficient of friction between the block $M$ and the horizontal surface,then the minimum value of $m_0$ required to keep the block $m$ stationary is

If ${\mu _s}$,${\mu _k}$,and ${\mu _r}$ are coefficients of static friction,sliding (kinetic) friction,and rolling friction respectively,then: