Answer:
voltage = -0.01116V
power = -0.0249W
Explanation:
The voltage v(t) across an inductor is given by;
v(t) = L
-----------(i)
Where;
L = inductance of the inductor
i(t) = current through the inductor at a given time
t = time for the flow of current
From the question:
i(t) = 
A
L = 10mH = 10 x 10⁻³H
Substitute these values into equation (i) as follows;
v(t) = 
Solve the differential
v(t) = 
v(t) = -0.05 
At t = 8s
v(t) = v(8) = -0.05 
v(t) = v(8) = -0.05 
v(t) = -0.05 x 0.223
v(t) = -0.01116V
(b) To get the power, we use the following relation:
p(t) = i(t) x v(t)
Power at t = 8
p(8) = i(8) x v(8)
i(8) = i(t = 8) = 
i(8) = 
i(8) = 10 x 0.223
i(8) = 2.23
Therefore,
p(8) = 2.23 x -0.01116
p(8) = -0.0249W
Answer:
The field strength needed is 0.625 T
Explanation:
Given;
angular frequency, ω = 400 rpm = (2π /60) x (400) = 41.893 rad/s
area of the rectangular coil, A = L x B = 0.0611 x 0.05 = 0.003055 m²
number of tuns of the coil, N = 300 turns
peak emf = 24 V
The peak emf is given by;
emf₀ = NABω
B = (emf₀ ) / (NA ω)
B = (24) / (300 x 0.003055 x 41.893)
B = 0.625 T
Therefore, the field strength needed is 0.625 T
Answer:
The surface temperature increases when two bodies are rubbed against each other due to friction.
Explanation:
No object has a perfectly even surface. So, when two bodies with uneven surfaces are rubbed against each other, they experience friction.
Friction is a resistance experienced by the two bodies when they are moved against each other.
The friction between the two surfaces, converts the kinetic energy of the movement to the thermal energy.
Thus, resulting in rise in the surface temperature of the two bodies.
Therefore, when two bodies are rubbed against each other, the surface temperature increases due to friction.
umm , is it okay if we do this on microsoft word , cuz i cant send pics of answers here...
