A student wanted to see if the color of water impacted the increase in temperature, in degrees
Celsius (°C), after 30 minutes in the Sun.
• three beakers were filled with 50 milliliters (ml) of water
• five drops of food coloring were added to each beaker (one beaker had 5 drops of red food
coloring, one beaker had 5 drops of blue and one beaker had 5 drops of green)
• the beakers were then placed on a window ledge in direct sunlight
• temperature readings were recorded every 10 minutes for 30 minutes
What was the test (independent) variable in this experiment?
the temperature of the water
the amount of water in each beaker
the color of the water
the amount of time each beaker was exposed to sunlight