Answer:
Candles
Explanation:
The answer is the first option or "candles." In ancient times the people would lit candles and place them in difference places in their homes, temples, etc... to produce light. It's not option B because light emitting diodes are used to light up toys and such which weren't invented in ancient times. It's not option C because fluorescent bulbs are long light bulbs used to light up huge spaces without as many light bulbs which were again not invented at the time, and it's also not option D because incandescent bulbs are you usual light bulbs which weren't invented at the time.
Hope this helps.
Answer:
energy can move from one location to another, the particles of matter in the medium return to their fixed position. A wave transports its energy without transporting matter.
Sin(90 + θ)
By addition angle formula for sine.
sin90cosθ + cos90sinθ
1*cosθ + 0*sinθ
cosθ + 0
= cosθ
sin(90 + θ) = cosθ
Answer: When chemical change occurs you will see like, the change of color or bubbles will form, the temperature will change, and maybe the odor too.
Answer:
Explanation:
#Consider a circular area of radius 
in the xy-plane at z=0. This means all the are vector points toward the +ve z-axis.
a. first, find the magnetic flux if the magnetic field has a magnitude of 
and points toward the +ve z-axis. The angle between the magnetic field and the area is 
. Hence the magnetic flux:-
Hence flux magnitude in 
direction is 
b. We now find the magnetic flux when the field has a magnitude of <em>B=0.230T</em> and points at an angle of 
from the direction.
Magnetic flux is calculated as:
Hence the flux at an angle of 
is 
c. We now need to find the magnetic flux if the field has a magnitue of B=0.230T and points in the direction of +y-direction. As with the previous parts, the magnetic flux will be calculated as:
Hence the magnetic flux in the +y-direction is zero.
