Answer:
0.73 N to 2 dp.
Step-by-step explanation:
F = k/d^2 where k is a constant , F = force and d = distance.
Substituting:
0.36 = k / (6)^2
k = 36*0.36 = 12.96 s the equation is F = 12.96 / d^2.
When d = 4.2 :
F = 12.96 / 4.2^2
F = 0.73 Newtons to 2 dp.
Answer:
4. x= 18
Step-by-step explanation:
We solve the problem like this:
Since 3 is proportional to 6 and 9 is proportional to x, we set up a proportion.
3/9 = 6/x
We then use cross-multiplication to solve for x.
Looks like you have most of the details already, but you're missing one crucial piece.
is parameterized by
for 
and 
, and a normal vector to this surface is
with norm
So the integral of 
is
