Why does my shadow change?

Have you ever wondered why shadows can be different shapes or change size during the day? 

Light tends to travel in straight lines, whether it be from the sun or from a torch or light. If we put an opaque object in front of the light, it blocks the light and creates a shadow. The size and shape of the object and how see-through it is will all change the way a shadow looks. This isn’t the only thing that changes a shadow, after all you don’t change size or shape, but your shadow keeps changing, doesn’t it?

The angle of light falling on an object can change the shadow too, think about your shadow on a sunny day. The sun is lower in the sky during the morning and afternoon, so your shadow will be longer and stretch away from you. Around midday, when the sun is higher in the sky, your shadow will be shorter almost like you are walking on top it. So that’s why our shadow keeps changing during the day, because the angle of the sunlight changes throughout the day.

Another thing that changes your shadow is the amount of light there is to make a shadow. Think about your shadow on a cloudy day when the sun is hiding behind the clouds. This makes the light from the sun more diffuse, less direct and this will change your shadow. Sometimes you may have a dark well-defined shadow and sometimes it will be very faint, almost invisible. Other things can change a shadow, the distance between the object and the light, the light source itself and the surface the shadow is cast on.

How illuminating!