Magnetic field outside solenoid

anthell

Instead of the usual

B = μ₀NI for field inside solenoid...

how should i go about finding the field let say... 10cm away from one end of the solenoid
1. directly at the z-axis
2. not directly at the z-axis

this is assuming the solenoid has finite length, finite number of turns ,finite radius
(ex. L = 25cm , R = 10cm, N = 1000, I = 1A)

Please help me out hehe thx

mfb

You can use the Biot–Savart law or some equations derived from that law.