Answer:
F=12.5N
Explanation:
Net force = rate of change of momentum

so find the change of momentum P
Pdown

Pup

dP = change in P

so
Answer:
force for start moving is 7.49 N
force for moving constant velocity 2.25 N
Explanation:
given data
mass = 7.65 kg
kinetic coefficient of friction = 0.030
static coefficient of friction = 0.10
solution
we get here first weight of block of ice that is
weight of block of ice = mass × g
weight of block of ice = 7.65 × 9.8 = 74.97 N
so here Ff = Fa
so for force for start moving is
Fa = weight × static coefficient of friction
Fa = 74.97 × 0.10
Fa = 7.49 N
and
force for moving constant velocity is
Fa = weight × kinetic coefficient of friction
Fa = 74.97 × 0.030
Fa = 2.25 N
Answer:

Explanation:
The magnetic field produced by a current-carrying wire is given by

where
is the vacuum permeability
I is the current
r is the distance from the wire
In this problem we have

r = 1.2 mm = 0.0012 m
So the magnetic field strength is

The awnser is. 1728000 kilometers