Omar wrote a hypothesis about batteries called dry cells. If more dry cells are connected end to end, a light bulb will work longer because there is more energy available. What are the variables in his hypothesis? The independent variable is the number of dry cells, and the dependent variable is the length of time the bulb works. The independent variable is the length of time the bulb works, and the dependent variable is the number of dry cells. The independent variable is the number of dry cells, and the dependent variable is the amount of energy available. The independent variable is the amount of energy available, and the dependent variable is the number of dry cells.

The independent variable is the number of dry cells and the dependent variable is the time the bulb works.

Explanation:

In this exercise, you are asked to analyze the variables derived from Ómar's hypotypeis

  "If more dry cells are connected end-to-end, a light bulb will work longer because more energy is available."

In this hypothesis, the independent variable that is controlled by the researcher is the number of batteries to be connected in series.

The dependent variable that is measured by the researcher is how long the bulbs last.

When reviewing the different answers, the correct one is:

The independent variable is the number of dry cells and the dependent variable is the time the bulb works.

5 w for 1hr = 5x60x60 joules=300x60=3000x6=18,000j as total energy conversion. efficiency of bulb needed for radiant to thermal within 18000