Problems Involving Shadows
Problems Involving Shadows
A shadow is a dark area where light from a light source is blocked by an opaque object. It occupies all of the three-dimensional volume behind an object with light in front of it. The cross section of a shadow is a two-dimensional silhouette, or a reverse projection of the object blocking the light.
Problems Involving Shadows : Shadows are formed when the person is obstructing the path of light. In the morning as the Sun rises from the East.
But in the evening as we know the sets in the West. All these directions will be reversed.
Illustration : In an evening when Suraj started walking from his house, his shadow was exactly towards his right. He walked 6 km. Then he turns to his left and moved 4 km. Again he turns to his right and walked 6 km. Then he turns to his right and moved 13 km. How far is he and in which direction from the starting point ?
A. 15 km North-East B. 15 km North C. 15 km South-East D. 16 km South E. 17 km East
Answer : A
Solution : In the evening when the Sun is in the West the shadow is in East In an evening when Suraj started walking from his house, his shadow was exactly towards his right. that means he is facing in North Direction.
The path he has traversed is shown in the figure below
The distance between A and E is calculated using pythagoras theorem
We see that AFE is a right angled triangle, right angled at F. So AE is the hypotenuse as it is the side opposite to right angle.
At sunrise, Rohit and Mohit are having a conversation standing in front of each other. The shadow of Mohit is formed towards the right hand of Rohit. What direction is Mohit facing? | |||
| Right Option : C | |||
| View Explanation | |||
In evening Amit covers 10 meters then turns in his left and cover 5 meters again he turns right and covers 3 meters and again he turns right and cover 5 meter finaly he turns left and cover 3 m. At this time his shadow in his right then in which direction he started his journey ? | |||
| Right Option : A | |||
| View Explanation | |||
Zooya walked in her left and covered a distance 20 m and than turns right and covers a distance of 10 m, and than turns left and covers a distance of 10 m , and again she turns right and covers a distance of 20 m , and than turns right and covers a distance of 60 m. and now, her shadow is formed just her back. At what time she is walking ? | |||
| Right Option : B | |||
| View Explanation | |||
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