Read the passage. a 40-ton creature was coming right at my boat, spinning round and round. we could hear his fins slapping the water with each revolution. the brute exhaled and salty water sprayed us before he dove again. the sight of his tail revolving around, barely missing the boat, sent shivers down my spine. when he came to the surface again, we could have counted the barnacles on his enormous head. what did the writer hear slapping the water?
the boat
the anchor
the barnacles
the fins

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: