Astudent spots an unknown sample on a tlc plate. after developing in hexanes/ethyl acetate 50: 50, he/she saw a single spot with an rf of 0.55. does this indicate that the unknown material is a pure compound? what can be done to verify the purity of the sample?

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation:

explanation:

v=uf/(u-f)

= 5.-10/(5+10) convex lens has negative focal length

it has to be b, about 97 percent.