Answer:
The value is 
Explanation:
From the question we are told that
The current is 
The radius is 
The length of the wire is 
\
The resistance is 
The outer surface temperature is 
The average thermal conductivity is 
Generally the heat generated in the stainless steel wire is mathematically represented as
=> 
=> 
Generally the middle temperature is mathematically represented as
Answer:
21.9 seconds
Explanation:
lets say the speed of sound at room temp 343m/s and one kilometer is 1000 meters. so 7.5 kilometers is equal to 7500 meters and we divide this number by 343 and we get 21.8 seconds
Answer:
Explanation:
Magnetic field at a a point R distance away
B = μ₀ / 4π X 2I / R where I is current
Magnetic field due to one current
= 10⁻⁷ x 2 x 24 / 1 x 10⁻³
48 x 10⁻⁴ T
Magnetic field due to other current
= 10⁻⁷ x 2 x 24 / 3x 10⁻³
16 x 10⁻⁴ T
Total magnetic field , as they act in opposite direction, is
= (48 - 16 ) x 10⁻⁴
32 x 10⁻⁴ T .
Answer:Electrons have negative charge.
Explanation:Electrons are designated to be the carriers of negative charge. The assignment of negative and positive to electrons and protons respectively can be attributed to Benjamin Franklin. He could have easily reversed this designation. Like all charged particles, negative charges create electric fields around them.
Let
V the speed of the girl per step
v the speed of the escalator per step
L the length between ground and floor in number of steps
V*60+v*60=L => V+v=L/60
V*90-v*90=L => V-v=L/90
By adding the equations V+v=L/60 and V-v=L/90 we get:
2V=L(3+2)/180
V=5L/360
V = L/72
Time to climb (in steps) with v=0 (escalator standing still) is:
V*t=L
t = L/V
t = L/(L/72)
t =72 steps
The girl will count 72 steps.
