If the mass of one of two particles is doubled and the distance between them is doubled, the force of attraction between the two particles will

The force of attraction between the two particles will become half.

Explanation:

Consider force F between two objects with masses m and m' which are placed r distance apart from each other.

Mass of first object = m

Mass of second object = m'

Distance between the  two objects = r

...(1) (Gravitational force)

If the mass of one of two particles is doubled and the distance between them is doubled the force between them be F'.

Mass of first object = m

New mass of second object = M = 2m'

Distance between the  two objects = R = 2r

...(2) (Gravitational force)

Dividing (1) from (2):

The force of attraction between the two particles will become half.

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: