When spotting an overhead press, the spotter would need to . A.
keep his or her hands off the lifter and weights and make sure the lifter did not fall back
B.
keep his or her hands beneath the bar and watch the bar carefully
C.
hold the lifter under his or her shoulders and move with the lifter as the weight is lifted
D.
place his or her hands outside the lifter's hands and stand with a straight back

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: