The equation for the resistance R is: R=ρ*(l/A), where, ρ is electrical resistivity, l is the length of the conductor, and A is the surface area.
The initial surface area is:
A=r²π, then when we double the radius we get:
A₁=(2*r)²π=4*r²π=4*A
Initial resistance is: R=ρ*(l/A).
When we double the radius, resistance is: R₁=ρ*{ l / (4*A) }
The ratio of the new resistance to the old one:
R₁/R=[ρ*(l/A)] / [ ρ* { l / (4*A) } ] = ρ, l and A cancel out and we get:
R₁/R=(1/1)/(1/4)=4/1
Answer:
(a) a = (2i + 4.5j) m/s^2
(b) r = ro + vot + (1/2)at^2
Explanation:
(a) The acceleration of the particle is given by:

vo: initial velocity = (3.00i -2.00j) m/s
v: final velocity = (9.00i + 7.00j) m/s
t = 3s
by replacing the values of the vectors and time you obtain:
![\vec{a}=\frac{1}{3s}[(9.00-3.00)\hat{i}+(7.00-(-2.00))\hat{j}]\\\\\vec{a}=(2\hat{i}+4.5\hat{j})m/s^2](https://tex.z-dn.net/?f=%5Cvec%7Ba%7D%3D%5Cfrac%7B1%7D%7B3s%7D%5B%289.00-3.00%29%5Chat%7Bi%7D%2B%287.00-%28-2.00%29%29%5Chat%7Bj%7D%5D%5C%5C%5C%5C%5Cvec%7Ba%7D%3D%282%5Chat%7Bi%7D%2B4.5%5Chat%7Bj%7D%29m%2Fs%5E2)
(b) The position vector is given by:

where vo = (3.00i -2.00j) m/s and a = (2.00i + 4.50j)m/s^2
Answer:
See below
Explanation:
Gallileo is CORRECT in a vacuum where there is<u> no air friction</u>
<u>air friction</u> affects same or different weight objects differently and will cause same-weight or different weight objects to fall at different speeds
Answer:
physic, is natural science of motion and behavior
Answer:
b -algae
Explanation:
The most common producers in aquatic ecosystems are the algae. They are called phytoplanktons.
- In the food web and food chain of aquatic ecosystems, they usually set out with the algae.
- These algae are called phytoplanktons.
- They are the producers in all aquatic ecosystem.
- Phytoplanktons consists of algae and cyanobacteria.
- Just like plants on land, phytoplanktons manufacture food in an aquatic ecosystem.