The rule that is used to get the strength of magnetic field at the center of solenoid (B) is:
B = <span>µ x n x I where:
</span>µ is the permeability of the medium where the solenoid is based. In this problem, the medium is air which means that µ = <span>µ </span><span>o = 4 pi x 10^-7 Tm/A
</span>I is the current passing (I = 4 amperes)
n is the number of turns per unit length (5000 turns)
Substituting in the mentioned equation, we find that:
B = 4 x 3.14 x 10^-7 x 5000 x 4 = 25.132 mT
Answer:
part(a) 151 m
part(b) 1.073 m/s2
part(c) 16.7 secs
Explanation:Firstly the person applied brakes 0.5 secs after seeing the red light hence the distance traveled during this time is
d=v*t
d=18*0.5
d=9m
For part (a)
I have corrected this question and now
The person was 160m from the intersection before applying the brakes as he traveled 9m before the brakes
He is now 151 m from intersection as
s=160-9
s= 151 m
part (b)
As it is given that velocity of the car is 0 at the intersection so we use this information in kinematic equation

here u=18m/s and s=151

To calculate time we can use the acceleration equation

Resistance decreases the flow of current in a circuit.
Explanation:
The resistance of an electrical circuit is defined as the opposition to the flow of current in that particular circuit
Answer : Option C) Heredity; Lifestyle.
Explanation : While some aspects are based on heredity, body composition is largely a result of Lifestyle.
Even though it is believed that 80 percent of the aspects of a human body is heredity, but an individual body composition is largely influenced by the result of the lifestyle an individual lives.