Answer:
Magnetic field, B = 0.23 T
Explanation:
Given that,
Length of the copper rod, L = 0.49 m
Mass of the copper rod, m = 0.15 kg
Current in rod, I = 13 A (in +ve y direction)
When the rod is placed in magnetic field, the magnetic force is balanced by its weight such that :

So, the magnitude of the minimum magnetic field needed to levitate the rod is 0.23 T.
Explanation:
Water (H2O) as a polar covalent molecule has its arrangement of oxygen and hydrogen atoms where one end (hydrogen) has a partially positive charge while the other side (oxygen) had a partially negative charge.
It is also capable of forming hydrogen bonds with polar molecules. Each water molecule can form two hydrogen bonds involving their hydrogen atoms and two further hydrogen bonds using the hydrogen atoms attached to neighboring water molecules.
I think the answer might be b
Other characteristic of radiation is the presence of positive and negative charge.
<h3 /><h3>What other characteristic does the radiation have?</h3>
Positive or negative charge are the other characteristic that is present in the radiation. Beta radiation have negative charge while on the other hand, alpha radiation have positive charge.
So we can conclude that other characteristic of radiation is the presence of positive and negative charge.
Learn more about radiation here: brainly.com/question/893656
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