An athlete completes one round of a circular track of diameter $49 \,m$ in $20 \,s$. Calculate the distance covered and displacement at the end of $30 \,s$.
Given $d=49 m , T =20 s , t=30 s$
At the end of $30 s$, rounds completed are
$n=\frac{30}{20}=1.5$
Therefore, distance travelled
$S=2 \pi r=2 \times \frac{22}{7} \times \frac{49}{2} \times 1.5=231 m$
Displacement is equal to the diameter $49 m$ as after the completion of $1.5$ rounds the athlete will be diametrically opposite to his point of start.
Write true or false for the following statements
Kinematics deals with the motion of non$-$living objects without taking into account the cause of their motion.
There are 5 houses on a street, $A, B, C, D$ and $E$. For all cases, assume that positions to the right are positive.
$(i)$ Draw a frame of reference with house $A$ as the origin and the positions of houses $B, C, D$ and $E$.
$(ii)$ You live in house $C.$ What is your position relative to house $E$ ?
$(iii)$ What are the positions of houses $A$ and $D$, if house $B$ is taken as the reference point ?
If the average velocity of a body is equal to mean of its initial yelocity and final velocity, then the acceleration of the body is
Define velocity.
What is the numerical ratio of average velocity to average speed of an object when it is moving along a straight path ?