Answer:
The magnetic field is 
Explanation:
From the question we are told that
The mass of the metal is 
The current is 
The distance between the rail(length of the rod ) is 
The coefficient of kinetic friction is 
Generally the magnetic force is mathematically represented as

Given that the rod is moving at a constant velocity, it
=> 
Where
is the kinetic frictional force which is mathematically represented as

So

=> 
substituting values
=> 
=> 
Answer:
Speed: 4.8 m/s
Velocity: 4.8 m/s north
Explanation:
Definitions:
- Speed is a scalar quantity, which is equal to the ratio between distance covered (d) and time taken (t):

- Velocity is a vector quantity, whose magnitude is equal to the ratio between the displacement of the object and the time taken:

And it also has a direction (the same as the displacement).
In this problem:
- The object travels a distance of
d = 105 m
In a time interval of
t = 22 s
So its speed is

- The displacement of the object is the same as the distance in this case, so still 105 m, covered in a time interval of 22 s; this means that the magnitude of the velocity is the same as the speed:

However, velocity is a vector quantity, so it also has a direction: and since the object has moved north, the direction of the velocity is north as well.
Answer:
F = 0
Explanation:
Newton's second law is
F = ma
As in this case the two blocks move with constant speed, it implies that the acceleration is zero, therefore the force applied to the system is zero
F = 0
I need a picture to help you