Answer:
Experimental: the dogs who get the toys
Control: the dogs who dont recieve a toy
Explanation:
expermental is the group that recieved the tested variable in this case that being the toy
control is the group that doesn't recieve the tested variable
Answer:
1.Physical. People measure water by themselves.
2.Physical. People chop wood.
Explanation:
(this is all I can answer for you. you have to explain it by yourself tho.)
I dont know if I'm correct so you should double check.
Answer:
Now length of body diagonal of this cube = √3×√2×r =2.45r
Explanation:
a) length of body diagonal of this cube = √3×√2×r = 2.45 r
it can solved as following
length of body diagonal = √3a (where a is edge length of cube)
length of face diagonal = √2a
But length of face diagonal = 2r
Therefore a = 2r /√2 = √2×r
Now length of body diagonal of this cube = √3×√2×r
Answer:
the stronger light 5.5 m apart from the total illumination
Explanation:
From the problem's statement , the following equation can be deducted:
I= k/r²
where I = intensity of illumination , r= distance between the point and the light source , k = constant of proportionality
denoting 1 as the stronger light and 2 as the weaker light
I₁= k/r₁²
I₂= k/r₂²
dividing both equations
I₂/I₁ = r₁²/r₂²=(r₁/r₂)²
solving for r₁
r₁ = r₂ * √(I₂/I₁)
since we are on the line between the two light sources , the distance from the light source to the weaker light is he distance from the light source to the stronger light + distance between the lights . Thus
r₂ = r₁ + d
then
r₁ = (r₁ + d)* √(I₂/I₁)
r₁ = r₁*√(I₂/I₁) + d*√(I₂/I₁)
r₁*(1-√(I₂/I₁)) = d*√(I₂/I₁)
r₁ = d*√(I₂/I₁)/(1-√(I₂/I₁)) =
r₁ = d/[√(I₁/I₂)-1)]
since the stronger light is 9 times more intense than the weaker
I₁= 9*I₂ → I₁/I₂ = 9 →√(I₁/I₂)= 3
then since d=11 m
r₁ = d/[√(I₁/I₂)-1)] = 11 m / (3-1) = 5.5 m
r₁ = 5.5 m
therefore the stronger light 5.5 m apart from the total illumination
