- Home
- Standard 9
- Science
7. MOTION
hard
The following graph describes the motion of a girl going to meet her friend who stays $50\, m$ from her house
$(i)$ How much time she takes to reach her friend's house ?
$(ii)$ What is the distance travelled by the girl during the time$-$interval $0$ to $12$ minute ?
$(iii)$ During which time-interval she is moving towards her house ?
$(iv)$ For how many minutes she was at rest, during the entire journey ?
$(v)$ Calculate the speed by which she returned home.
Option A
Option B
Option C
Option D
Solution
$(i)$ $14$ minute.
$(ii)$ $40 m +20 m =60 m$.
$(iii)$ Between $14$ to $16$ minutes.
$(iv)$ $2+2+2=6$ minutes.
$(v)$ Speed $=\frac{\text { Total distance covered }}{\text { Total time taken }}$
$=\frac{50 m }{2 min }=25 m \min ^{-1}$
$=\frac{25 \times 60}{1000} kmh ^{-1}=1.5 km h ^{-1}$
Standard 9
Science
