Question

An object travels 20 m in 2 s and then another 16 m in 2 s. What is the average speed of the object?

Answer 1

Explanation:

Distance1 = 20 m

Time1 = 4 s

Distance2 = 20 m

Time 2 = 10 s

Total Distance(D) = 20m + 20m = 40m

Total Time(T) = 4s + 10s = 14s

Average Speed = Total Distance(D) / Total Time(T) = D/T = 40/14

= 2.857 m/s

Answer 2

Given: Distance traveled by the object, d₁= 20m, and d₂ = 16m

           Time taken by the object, t₁ = 2s, and t₂= 2s

To Find: Average speed of the object, S.

Solution :

To calculate S, the formula used :

• average speed of an object is the total distance covered by it per unit of the total time taken by it.

• Average speed = total distance covered / total time taken

• S = d₁ + d₂ / t₁ + t₂

Applying the above formula-

S = 20 + 16 / 2 +2

  = 36/4

  = 9 m/s

S = 9 m/s

Hence, average speed of the object is 9 m/s.