Answer:
the net force applied to the car is zero.
Explanation:
According to Newton's second law, the acceleration of an object (a) is directly proportional to the net force applied (F):
where m is the object's mass.
In this problem, the car is moving with constant velocity: this means that the acceleration is zero, a = 0. Therefore, according to the previous equation, the net force must also be zero: F = 0. So, the correct answer is
the net force applied to the car is zero.
Answer:
200A
Explanation:
Given that
the distance between earth surface and power cable d = 8m
when the current is flowing through cable , the magnitude flux density at the surface is 15μT
when the current flow throught is zero the magnitude flux density at the surface is 20μT
The change in flux density due to the current flowing in the power cable is
B = 20μT - 15μT
B =5μT -----(1)
The expression of magnitude flux density produced by the current carrying cable is
-----(2)
Substitute the value of flux density
B from eqn 1 and eqn 2
Therefore, the magnitude of current I is 200A