Answer:
1 and 3
Explanation:
<u>1 and 3 </u>
Increasing coils increases strength
COOLING the wire would increase current flow and strength of magnet
Adding an iron core will definitely increase the strength of the electromagnet
Answer:
The number of atoms is 
Explanation:
From the question we are told that
The mass of coin is 
Number of atom in one mole = 
Molar mass of nickel 
Now the relation to obtain the number of atom in the nickel coin is



Wound it be one that dissolves ?
Answer:
The ball has kinetic energy
the kinetic energy is 945 J
Explanation: