Answer:
Explanation:
Reddening of sun's rays at sunset and sunrise is due to scattering of light . The white light consisting of seven colours coming from the sun are scattered in different directions when they fall on the air particles present in atmosphere . Red coloured light scatters least and it travels straight forward to the viewer on the earth . On the other hand other colours scatter most and therefore they go out of area of vision for the viewer on the earth . Since only red colour reaches the eye of the viewer , sun's ray appear red . This happens during sunrise and sunset . It is so because during this period , sun rays travel far greater distance through atmosphere , so scattering is most pronounced .
Answer:
Explanation:
Area A of the coil = .1 x .1 = .01 m²
no of turns n = 5
magnetic field B = .5 t²
Flux Φ perpendicular to plane passing through it.= nBA sin30
rate of change of flux
dΦ/dt = nAdBsin30 / dt
= nA d/dt (.5t²x .5 )
= nA x 2 x .25 x t
At t = 4s
dΦ/dt = nA x 2
= 5x .01 x 2
= .1
current = induced emf / resistance
= .1 / 4
= .025 A
= 25 mA.
Answer:
- The emf of the generator is 6V
- The internal resistance of the generator is 1 Ω
Explanation:
Given;
terminal voltage, V = 5.7 V, when the current, I = 0.3 A
terminal voltage, V = 5.1 V, when the current, I = 0.9 A
The emf of the generator is calculated as;
E = V + Ir
where;
E is the emf of the generator
r is the internal resistance
First case:
E = 5.7 + 0.3r -------- (1)
Second case:
E = 5.1 + 0.9r -------- (2)
Since the emf E, is constant in both equations, we will have the following;
5.1 + 0.9r = 5.7 + 0.3r
collect similar terms together;
0.9r - 0.3r = 5.7 - 5.1
0.6r = 0.6
r = 0.6/0.6
r = 1 Ω
Now, determine the emf of the generator;
E = V + Ir
E = 5.1 + 0.9x1
E = 5.1 + 0.9
E = 6 V
"Traditionally, physical science courses are categorized into four areas: physics, chemistry, earth sciences, and space sciences. It is important to understand that the arbitrary divisions of specialized knowledge are integrated into a basic overview of the physical laws that govern our universe." - Cameron University
The fibers have lost electrons giving them a positive charge. The rubber gained electrons giving it a negative charge. The positively charged fibers are now attracted to the negatively charged balloon. The negatively charged balloon attracts the paper.
