Question

Richa walks 4km in the direction of the sun on sunset time. Then she turns right and walks 1km. She turns left and walks 1km then she turns left and walks 1km. Find displacement of her walk in km?
A) $3$
B) $4$
C) $5$
D) $6$

Answer 1

Hint:
We can solve this question, by drawing the path and the directions taken by Richa on a piece of paper and imagining ourselves in the place of Richa so that we could easily think that which direction is her left and which is her right. After drawing the whole path, we would try to find the shortest distance between the starting and the end point and hence, we would find the required answer.

Complete step by step solution:
To find the displacement of Richa’s walk in km, we should try to draw the turns taken by her on a piece of paper.
First of all, assume a starting point and let it be A.
Now, according to the question, Richa walks 4km in the direction of sun on sunset time i.e. West.
So,
We would draw a straight line which shows 4 km .
Then it is given that she turns right and walks 1km. Hence, we would extend the line towards right showing 1 km.
Again, She turns left and walks 1km, hence, we would think from the point where we have stopped that which direction is our left as if we are going towards that direction.
Similarly, she again turns left and walks 1km, hence the diagram would be like this:

Now, we are required to find the displacement of her walk in km.
As we can see clearly from the diagram, the distance between her starting point and end point is a straight line, i.e.
4 km $ + $1 km
$ = 5$km
Hence, displacement of her walk is 5 km.

Therefore, option C is the correct answer.

Note:
Since, we are required to find the displacement of her walk in km, we should know the meaning of displacement. As from our previous knowledge, displacement is the shortest distance possible between two endpoints. Hence, in this question, after drawing the whole path, we are required to join the starting and the end point and add the total distance between the two, hence, we would get the required answer. The most common mistake which we can make in these types of questions is taking a ‘left’ instead of ‘right’ and vice-versa. Hence, these questions should be solved carefully and attentively.