Name: Making Your Own Sundial
Uploaded: 2019-07-19
Duration: 4 min 15 s
Description: Sundial is a device that tells the time of day by sunlight, how time can be evaluated by a sundial and how it works. Let's learn in the video.

Question

A boy covered

4 km

to reach the market in

2 hours

and returned home in

2 hours

. What is his average speed?

Accepted Answer

The distance travelled by the boy from home to the market is, $s_{1} = 4 km$ .
The time taken by the boy to reach the market, $t_{1} = 2 hr$ .
The distance travelled by the boy from the market to the home back is, $s_{2} = 4 km$ .
The time taken by the boy to reach home from the market, $t_{2} = 2 hr$ .
Now, according to the definition, the average speed is the total distance travelled by the body by the total time taken i.e. It is a scalar quantity.
$Average speed = \frac{Total distance}{Total time taken}$
The total distance is $s_{1} + s_{2} = 4 + 4 = 8 km$ , The total time taken is $t_{1} + t_{2} = 2 + 2 = 4 hr$ .
$Average speed = \frac{8 km}{4 hr} = 2 km {hr}^{- 1}$ .
Hence, the average speed of the boy is $2 km {hr}^{- 1}$ from home to the market and back to the home.

A boy covered $4 km$ to reach the market in $2 hours$ and returned home in $2 hours$ . What is his average speed?

Important Questions on Time and Motion

Learn and Prepare for any exam you want !

A boy covered 4 km to reach the market in 2 hours and returned home in 2 hours. What is his average speed?

Important Questions on Time and Motion

Learn and Prepare for any exam you want !

A boy covered $4 km$ to reach the market in $2 hours$ and returned home in $2 hours$ . What is his average speed?