Answer:
The rotation of a planet around it's sun
I don’t know what book you’re talking about so I can’t help but have a look online, you may be able to find it if you search up the book name and look around a few websites
Answer:

Explanation:
We are given that
Current in wire=40 A
Magnetic field=
T( vertically downward)
We have to find the resultant magnitude of the magnetic field 29 cm above the wire and 29 cm below the wire.
According to Bio-Savart law, the magnetic field exerted by the wire at distance R is given by

We have R=29 cm=
1 m=100 cm
Substitute the values in the given formula

The resultant magnetic field is given by

Substitute the values then we get


The resultant magnitude of magnetic field is same above and below the wire as it is at same distance.
The resultant magnitude of the magnetic field 29 cm below the wire=
Hence, the resultant magnitude of the magnetic field 29 cm above the wire=