D. Saturn, Jupiter and Uranus
This is the substance(s) formed in a chemical reaction. is called the products
Here I =0.4 amp and t=2hr or 2×60×60 sec
We known I=nQ/t where Q is charge and n is no of charge.
n=It/Q
0.4x(2x60x60)/1.6x10^-19
Answer:
the engine cool to 40
at 14.07 minutes
Explanation:
Given information
T(5) = 70
= 100
C = 15
Newton's law of cooling :
T(t) = C + ( - C) 
where
T(t) = temperature at any given time
C = surrounding temperature
= initial temperature of heated object
k = cooling constant
to find the the time when the engine will be cooled down to 40, we first need to find the cooling constant, k
when t = 5, T(5) = 70
so,
T(t) = C + ( - C)
T(5) = 15 + (100 - 15) 
70 = 15 + (85)
= (70 - 15) / 85
-5k = ln (55/85)
k = - ln (55/85) / 5
k = 0.087
thus, we have the eqaution
T(t) = 15 + (85) 
now we can determine the time when T(t) = 40
40 = 15 + (85)
= (40-15)/85
-0.0087t = ln (25/85)
t = - ln (25/85)/0.087
t = 14.07 minutes
Answer:
The gravitational force between them increases by a factor of 4
Explanation:
Gravitational force is a force of attraction between two objects with masses M and m which are separated by a distance R. It is given mathematically as:
Fg = GMm/R²
Where G = Gravitational constant.
If the distance between their centers, R, decreases by a factor of 2, then it means the new distance between their centers is:
r = R/2
Hence,the gravitational force becomes:
Fg = GMm/r²
Fg = GMm/(R/2)²
Fg = GMm/(R²/4)
Fg = 4GMm/R²
Hence,the gravitational force increases by a factor of 4.
