Light & Energy
This is how light causes materials to change (like fading or warming).
What is taking in energy?
When light bounces off a surface.
What is reflection?
If UV is absorbed but X-rays pass through, only this can cause change.
What is ultraviolet light?
A black T-shirt is left outside in the sun and becomes very warm. Why does this happen?
a. The shirt reflects all the light, causing it to heat up
b. The shirt absorbs energy from the light, causing it to warm up
c. The light pulls energy out of the shirt
d. The light carries heat molecules into the shirt
This determines the type of light (not amplitude).
What is wavelength?
This happens when a rug fades in sunlight.
What is absorbing energy from light?
When light passes through a material.
What is transmission?
A metal absorbs infrared light—will it warm up? If so, why?
What is yes, because it absorbs energy?
Sofia shines two types of light on a material. Red light is reflected, and blue light is absorbed. Which light is more likely to cause a change in the material?
a. Red light, because it bounces off
b. Both equally
c. Neither will cause a change
d. b. Blue light, because it is absorbed
If two lasers have different wavelengths, they are this.
What are different types of light?
This must happen for an object to warm up from light.
What is absorb light energy?
When light is taken in by a material.
What is absorption?
A butterfly wing glows under light only if this happens.
What is it absorbs the light energy?
Plastic melts in sunlight but not under a lamp because of this difference.
What is the type/amount of energy in the light?
Changing amplitude changes this, not the type.
What is brightness/intensity?
Different types of light can cause this—like warming OR changing color.
What are different changes to materials?
This type of light interaction is most likely to cause a material to heat up.
What is absorption?
Whether light changes a material depends MOST on this interaction.
What is whether the light is absorbed?
A student says, “Light cannot change objects because it is not made of matter.” Which is the best response?
a. The student is correct
b. Light can only warm objects, not change them
c. Light carries energy that can be absorbed and cause changes
d. Light pulls energy out of objects
All lasers give off the same type of light—true or false?
What is false?
If green light is reflected and red light is absorbed, this color will most likely be seen.
What is green?
If light is reflected or transmitted, this will NOT happen.
What is a change in the material (like heating or color change)?
This type of light is commonly associated with heat.
A student observes that a material does not change when light shines on it. What is the MOST likely reason?
a. The material reflects or transmits the light
b. The light has no energy
c. The light pulls energy out
d. The material is too strong to change
A material absorbs red and yellow light—this means the object will…
What is it can change (possibly in different ways)?