$A$ block is lying at rest inside a bus. What is the maximum acceleration of the bus such that the block remains stationary? (The static friction coefficient $\mu = 0.2$,acceleration due to gravity $g = 10 \ m/s^2$)

Find the apparent weight of a body of mass $1.0 \,kg$ falling with an acceleration of $10 \,ms^{-2}$. $\left(g \approx 10 \,ms^{-2}\right)$

An elevator car,whose floor-to-ceiling distance is $2.7 \, m$,starts ascending with a constant acceleration of $1.2 \, m/s^2$. $2 \, s$ after the start,a bolt begins falling from the ceiling of the car. The free-fall time of the bolt is ......... $s$.

$A$ box of mass $m \, kg$ is placed on the rear side of an open truck accelerating at $4 \, m/s^2$. The coefficient of friction between the box and the surface below it is $0.4$. The net acceleration of the box with respect to the truck is zero. The value of $m$ is :- $[g = 10 \, m/s^2]$

Two bodies of masses $m_1$ and $m_2$ are connected by a light string which passes over a frictionless,massless pulley. If the pulley is moving upward with uniform acceleration $\frac{g}{2}$,then the tension in the string will be .........

$A$ girl drops an apple from the window of a train which is moving on a straight track with speed increasing at a constant rate. The trajectory of the falling apple as seen by the girl is