Which of the following is a contact force? O A. Electrical force
O B. Friction
O C. Magnetic force
O D. Gravity

friction

Explanation:

all of the other forces can interact without physical contact

porque la cantidad de gases de efecto invernadero alcanzó un nuevo máximo sin precedentes, causando daños muy graves a esta, por eso es importante monitorearla, para controlar el porcentaje de daños que esta causa y poder reducirlo o mantenerlo.

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: