micrometer is used to measure the diameter of a thin wire
Balance and beaker of water. The balance will measure mass and the beaker will measure the volume when you take the initial volume without the key subtracting that value from the value with the key in the beaker
The correct answer is the Type of batteries
Explanation:
In an experiment, it is normal the researcher modifies one variable, in this case, the number of batteries (independent variable), and this variable affects the variable tested, in this case, the brightness of the bulb (dependent variable).
However, other factors or variables should be constant to guarantee the results are reliable. In this context, one factor that the student should keep constant is the type of batteries he uses because this is not one of the main variables and therefore it is not expected he changes this on purpose or this is affected by other variables. Moreover, by making any change the experiment can be negatively affected. For example, batteries might differ in their power capacity this can affect the brightness of the bulbs.
Answer:
28.57 cm
Explanation:
We are given that
Focal length,
Distance of application from his eyes,s=40 cm
s=25 cm
Substitute the values
