Question

a straight, 2.5-m wire carries a typical household current of 1.5 a (in one direction) at location where the earth's magnetic field i 0.55 gauss from south to north at a location where the earth's magnetic field is 0.55 gauss from south to north. find the magnitude and direction of the force that our planet's magnetic field exerts on this wire if it is oriented so that the current in it is running (a) from west to east, (b) vertically upward, (c) from north to south. (d) is the magnetic force ever large enough to cause significant effects under normal household current of 1.5 A

Answer 1

Answer:

a

The magnitude of the force is  $F=2.1*10^{-4}N$

The direction is from south to north i.e upward

b

The magnitude of the force is  $F=2.1*10^{-4}N$

The direction is towards the west

c

The magnitude of the force is  $F=2.1*10^{-4}N$

the direction of the magnetic field is parallel to the direction of the current  (south to north ) hence the direction in 0 in comparison to the direction of the current

d

From the value of force  we got the answer to this question is No

Explanation:

Generally magnetic force is mathematically represented as

                  $F = BIL$

Where the B is the magnitude of the magnetic field which is given as

          $B= 0.55 guass = \frac{0.55}{10000} = 0.55 *10^{-4}T$

               $I$ is the current with a value of $I = 1.5A$

               L is the length of the wire given as  $L =2.5m$

Substituting the value

             $F =(0.55 *10^ {-4}) (1.5)(2.5)$

                $F=2.1*10^{-4}N$

For the first case where the current is moving from west to east and we are told that the magnetic field is  from south to north the according to Fleming's right hand rule the force(exerted by earths magnetic field ) would be moving from south to north (i.e upward)

For the second case where current is moving vertically upwards the direction of the force is  to the west according to Fleming's right hand rule

 

Answer 2

Answer:

a) When the current is from west to east and the magnetic field is from south to north the magnitude of the force is 2.1x10⁻⁴N and the direction is upwards.

b) The current is moving vertically upward, the magnitude of the force is 2.1x10⁻⁴N and the direction is west.

c) The force is 0 because the magnetic field and the direction of the current are in parallel.

d) No, the force is less.

Explanation:

Given:

L = length of the wire = 2.5 m

i = current in wire = 1.5 A

B = magnetic field = 0.55x10⁻⁴T

a) The magnitude of magnetic force is equal to:

$F=BiL=0.55x10^{-5} *1.5*2.5=2.1x10^{-4} N$

b) The same way to a):

F = 2.1x10⁻⁴N

c) F = 0

The magnetic field and the direction of the current are in parallel.

d) The answer is no, the force is less