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$(a)$ Define circular motion.
$(b)$ "Uniform circular motion is an accelerated motion". Justify this statement with reason.
$(c)$ An artificial satellite is moving in a circular orbit of radius $42250\, km.$ Calculate its speed if it takes $24$ hours to revolve once around the earth.
Solution
$(a)$ If a body is moving along a circular path, then the body is said to be in circular motion.
$(b)$ Circular motion is an accelerated motion because the direction of its velocity is continuously changing but the magnitude of its velocity remains same.
$(c)$ Distance covered in one revolution
$2 \pi r=2 \times 3.14 \times 42250=265330\, km , t=24$ hour
Therefore, Speed $=\frac{\text { Distance }}{\text { Time }}=\frac{265330}{24}$
$=11055.42 km h ^{-1}$
Similar Questions
The following table show os the positon of three persons between $8.00\, am$ to $8.20\, am$.
| Time | Position (in $km$) | ||
| Person $A$ | Person $B$ | Person $C$ | |
| $8.00 \,am$ | $0$ | $0$ | $0$ |
| $8.05 \,am$ | $4$ | $5$ | $10$ |
| $8.10\, am$ | $13$ | $10$ | $19$ |
| $8.15 \,am$ | $20$ | $15$ | $24$ |
| $8.20\, am$ | $25$ | $20$ | $27$ |
$(i)$ Who is moving with constant speed ?
$(ii)$ Who has travelled maximum distance between $8.00\, am$ to $8.05\, am$ ?
$(iii)$ Calculate the average speed of person $'A^{\prime}$ in $k m h^{-1}$
