The direction of the magnetic field around the wire is counterclockwise when viewed from above the wire. This is known as the right-hand rule, where you point your right thumb in the direction of the current and your fingers curl in the direction of the magnetic field.
Increasing the current in the wire will increase the strength of the magnetic field. The strength of the magnetic field is directly proportional to the current, so doubling the current to four amps will result in a magnetic field twice as strong.
The strength of the magnetic field decreases as the distance from the wire increases. This relationship follows the inverse-square law, where the strength of the magnetic field is inversely proportional to the square of the distance from the wire.
Yes, the direction of the magnetic field can be reversed by changing the direction of the current. If the current is changed from flowing in the positive direction to flowing in the negative direction, the direction of the magnetic field will also reverse.
The presence of other objects or wires can alter the shape and strength of the magnetic field around the wire. This is because magnetic fields can interact with each other and may cancel out or reinforce each other depending on their orientation and strength.