A. 3.6 sec
B. 18 sec
C. 36 sec
D. 72 sec
Submitted by: Shuaib Uddin
Explanation
With 5 best steps
1.Data:
Speed 1=V₁= 9km/h
Distance 1=S₁= 240 m
Distance 2 =S₁= 120 m
Speed 2=V₂= 45km/h
Relative speed(V) = V₂_V₁
Relative speed (V)= 45km/h_9 km/h
Relative speed (V)=36km/h
Relative speed(V)= 36×1000m/3600Sec
Relative speed (V)= 36000m/3600Sec
Relative speed(V)= 10 m/sec
Covered distance(S)= 240m+120m
Covered distance (S)= 360m.
2. Required:
Time taken= T=??
3. Formula:
S= V×T
For T
T = S/V
4. Solution:
Putting values in formula.
T= 360 m/10 m/Sec
T= 36Sec
5. Result:
Time taken= T= 36 Sec