Question

an object is moving at the speed of 10 metre per second for 5 seconds, speed of 5 metre per second for 5 second, find its average speed

Answer 1

Average speed= total distance travelled/ total time taken
Let the distance travelled at the speed of 10m/s be d1 and distance travelled at the speed of 5m/s be d2,
Then d1= speed *time = 10 m/s *5 s = 50 m
and d2= speed * time =5m/s * 5 s= 25m
Total distance travelled = d1+d2 =75 m
total time taken= 5s +5s =10 s
So, avg. speed= 75/10 = 7.5 m/s

Answer 2

Hey there !

Speed = 10 m/s
time = 5 sec
distance = d₁ = speed x time
= 10 × 5 = 50 m

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speed = 5 m/s
time = 5 sec
distance = d₂ = speed x time
= 5 × 5 = 25 m

Total distance traveled = d₁ + d₂ = 25 + 50 = 75 m

`Total time = 5 + 5 = 10 sec


Average speed = total distance traveled / total time taken

= 75 /10
= 7.5 m/s