Answer
given,
mass of copper rod = 1 kg
horizontal rails = 1 m
Current (I) = 50 A
coefficient of static friction = 0.6
magnetic force acting on a current carrying wire is
F = B i L
Rod is not necessarily vertical
the normal reaction N = mg-F y
static friction f = μ_s (mg-F y )
horizontal acceleration is zero
B_w = B sinθ
B_d = B cosθ
iLB cosθ= μ_s (mg- iLB sinθ)
B = 0.1 T
Answer:
Resistance will become 4 times the previous value
Explanation:
We have given current in the circuit i = 2.4 A
According to ohm's law current in the circuit is given by 
So 
............eqn 1
Now voltage is increased to 4 times so new voltage = 4 V
And current in the circuit is same as 2.4 A
We have to fond the resistance so that after increasing voltage current will be same
So 
..........eqn 2
Dividing eqn 1 and 2
So resistance will become 4 times the previous value
Answer:
The circular loop experiences a constant force which is always directed towards the center of the loop and tends to compress it.
Explanation:
Since the magnetic field, B points in my direction and the current, I is moving in a clockwise direction, the current is always perpendicular to the magnetic field and will thus experience a constant force, F = BILsinФ where Ф is the angle between B and L.
Since the magnetic field is in my direction, it is perpendicular to the plane of the circular loop and thus perpendicular to L where L = length of circular loop. Thus Ф = 90° and F = BILsin90° = BIL
According to Fleming's left-hand rule, the fore finger representing the magnetic field, the middle finger represent in the current and the thumb representing the direction of force on the circular loop.
At each point on the circular loop, the force is always directed towards the center of the loop and thus tends to compress it.
<u>So, the circular loop experiences a constant force which is always directed towards the center of the loop and tends to compress it.</u>
