Hey, I think someone should help u cause I’m stuck too
Hope this helps !
Answer
D) burning a candle
Explanation
When burning a candle no new substance is form.
We have both physical and chemical change occuring.
Physical part: Melting of the solid wax and evaporation of the liquid forms the physical change.
Chemical part: burning of the wax vapour forms the chemical change.
Answer:
I think no 3 is false
and 4 is true
and the the ones you did are correct
if wrong correct me pls
Answer:
Approximately 0.0898 W/m².
Explanation:
The intensity of light measures the power that the light delivers per unit area.
The source in this question delivers a constant power of 
. If the source here is a point source, that of power will be spread out evenly over a spherical surface that is centered at the point source. In this case, the radius of the surface will be 9.6 meters.
The surface area of a sphere of radius 
is equal to 
. For the imaginary 9.6-meter sphere here, the surface area will be:
.
That power is spread out evenly over this 9.6-meter sphere. The power delivered per unit area will be:
.
Answer:
Solution
λ=v/n
Here, v=344 m s−1
n=22 MHz =22×106 Hz
λ=344/22×106=15.64×10−6m=15.64μm.
