A mass is suspended from the roof of a car by a string. While the car has a constant acceleration $a$, the string makes an angle of ${60}^o$ with the vertical. If $g=10m/s^2$, the value of $a$ is:

Q. A pendulum is suspended from the roof of a car. The car is moving with an acceleration of $49cm/s^2$. The angle which its string makes with the vertical is:

Q. A car is moving on a plane inclined at ${30}^{\circ }$ to the horizontal with an acceleration of $98m/s^2$ parallel to the plane upward. A bob is suspended by a string from the roof. The angle (in degrees) which the string makes with the vertical is: (Assume that the bob does not move relative to car) $[g=9.8m/s^2]$

Q. Find the value of acceleration of block $B$ (in ${\text{m/s}}^2$) for the system shown in figure. Take $g=10{\text{m/s}}^2$.

Q. Find the acceleration of block $A$ and $B$? Take $g=10m/s^2$