$A$ particle is moving on a circular path with constant speed,then its acceleration will be

$A$ car is travelling at $30 \,ms^{-1}$ speed on a circular road of radius $300 \,m$. If its speed is increasing at the rate of $4 \,ms^{-2}$, then its acceleration is (in $\,ms^{-2}$)

$A$ stone is tied to one end of a string $50\, cm$ long and is whirled in a horizontal circle with a constant speed. If the stone makes $10$ revolutions in $20\, s$,what is the magnitude of the acceleration of the stone in $cm/s^2$?

$A$ car is moving on a circular path of radius $500 \ m$ with a speed of $30 \ m/s$. If the speed is increasing at a rate of $2 \ m/s^2$,the net acceleration will be ......... $m/s^2$.

Tangential acceleration of a particle moving in a circle of radius $1 \, m$ varies with time $t$ as shown in the graph (initial velocity of the particle is zero). The time after which the total acceleration of the particle makes an angle of $30^{\circ}$ with the radial acceleration is:

Is the tangential acceleration of a particle moving in a circular path always zero? Under what condition is it zero?