Question

A person walks 60 meters in 1 minute. Then walks 30 meters in 2 minutes. What is their average speed over the 3minutes walk

Answer 1

Given :

▪ Distance covered in first min = 60m

▪ Distance covered in another two min = 30m

To Find :

▪ Average speed of person.

Concept :

❄ Average speed is defined as the ratio of total distance travelled to the total time taken.

❄ It is a scalar quantity.

❄ It can't be negative or zero.

❄ It has only magnitude.

❄ SI unit : m/s

Conversion :

➡ 1min = 60s

➡ 3min = 3×60 = 180s

Calculation :

$\mapsto\sf\:V_{av}=\dfrac{d_1+d_2}{t_1+t_2}\\ \\ \mapsto\sf\:V_{av}=\dfrac{60+30}{180}\\ \\ \mapsto\sf\:V_{av}=\dfrac{90}{180}\\ \\ \mapsto\underline{\underline{\bf{V_{av}=0.5mps}}}$

Answer 2

Given:

• A person walks 60m in a minute
• 30m in 2 minutes

To find:

• Average speed over 3 minutes walk

Conversion:

→ 1 min = 60s

→ 3 min = 180s

Solution:

Finding total distance & total time of person in a minute

→ Total distance = 60m + 30m = 90m

→ Total time = 1min + 2min = 3min= 180s

Now,

Average speed = Total distance/Total time

→ Avg speed = 90/180

→ Avg speed = 0.5 m/s

Hence, average speed = 0.5 m/s