deletions | additions       diff --git a/The_apparatus_has_two_different__.tex b/The_apparatus_has_two_different__.tex  index c864eea..4e226a9 100644  --- a/The_apparatus_has_two_different__.tex  +++ b/The_apparatus_has_two_different__.tex 
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The apparatus has two different field coils: 1) gradient Helmholtz  coils, and 2) Helmholtz gradient  coils. The Helmholtz coils produce a region of uniform magnetic field using two solenoid electromagnets on the same axis. The Helmholtz coils can be used to cancel external magnetic fields. In this experiment, we will use the Helmhotz coils to provide the field for experiments on 2H nuclei. The gradient coils distort the magnetic field in a predictable pattern. There are three sets of gradient coils: 1) x-component, 2) y-component, and 3) z-component. The z-component varies linearly along in  each direction. In this experiment, the gradient coils will allow for the measurement of the spin-lattice relaxation time, time  and homogenize the local Earth's magnetic field.