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.
In morning Roshan cover 20 meters then he turn to his left and cover 20 meters. Again he turns left and moves 5 meter. If at that time his shadow was towards his right then in which direction he started his journey ? | |||
| Right Option : B | |||
| View Explanation | |||
One morning Mohan and Gaurav were standing opposite to each other. Mohan's shadow fell exactly on his left. Toward which direction was Gaurav facing. | |||
| Right Option : A | |||
| View Explanation | |||
One morning after sunrise, Suresh was standing facing a pole. The shadow of the pole fell exactly to his right. To which direction was he facing? | |||
| Right Option : D | |||
| View Explanation | |||
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