Question

An object travels 20 metre in 4 seconds and then another 20 metre in 2 seconds. What is the average speed of the object?

Answer 1

▶ Solution :

Given :

An object travels first 20m in 4s and second 20m in 2s.

To Find :

Average speed of the object.

Concept :

Average speed of body is defined as ratio of total distance covered to the total time taken.

Mathematically,

$\boxed{\bf{\pink{\overline{V}=\dfrac{Total\:distance\:travelled}{Total\:time\:taken}}}}$

Calculation :

$\implies\sf\:\overline{V}=\dfrac{20+20}{4+2}\\ \\ \implies\sf\:\overline{V}=\dfrac{40}{6}\\ \\ \implies\boxed{\bf{\orange{\overline{V}=6.67\:mps}}}$

Additional information :

✴Average speed is a scalar quantity.

✴ It has only magnitude.

✴ Average velocity is a vector quantity.

Answer 2

Given that, an object moves 20 metre in 4 seconds.

So, distance (d1) = 20 m and time (t1) = 4 sec

Also given that, then object travels in 20 metre in 2 seconds.

Now, distance (d2) = 20 m and time (t2) = 2 sec

We have to find the average speed of the object.

Average speed = (Total distance)/(Total time)

Total distance travelled by an object = d1 + d2

= (20 + 20)m

= 40 m

Total time taken by an object = t1 + t2

= (4 + 2) sec

= 6 sec

Average speed = 40/6 = 6.67 m/s

Therefore, the average speed of the object is 6.67 m/s.