Answer:
In a controlled experiment, an independent variable (the cause) is systematically manipulated and the dependent variable (the effect) is measured; any extraneous variables are controlled. The researcher can operationalize (i.e. define) the variables being studied so they can be objectivity measured.
Answer:
To create an electric potential difference between the ends of the conductor.
Explanation:
For current to flow, there must exist an electric potential difference between the ends of the conductor. This PD is provided by the electromotive force stored within the battery. Unless there is a connection between the terminals no PD will exist between the terminals.
Answer:
Explanation:
Given
Two masses
and
is released and there is tension T in the string
Suppose a is the acceleration of the system
Therefore from Diagram
For 

------1
for m_2 body

-------2
From above two Equation it is said that Tension is greater than m_1g and less than m_2g
