Answer: 0.258
Explanation:
The resistance
of a wire is calculated by the following formula:
(1)
Where:
is the resistivity of the material the wire is made of. For aluminium is
and for copper is 
is the length of the wire, which in the case of aluminium is
, and in the case of copper is 
is the transversal area of the wire. In this case is a circumference for both wires, so we will use the formula of the area of the circumference:
(2) Where
is the diameter of the circumference.
For aluminium wire the diameter is
and for copper is 
So, in this problem we have two transversal areas:
<u>For aluminium:</u>

(3)
<u>For copper:</u>

(4)
Now we have to calculate the resistance for each wire:
<u>Aluminium wire:</u>
(5)
(6) Resistance of aluminium wire
<u>Copper wire:</u>
(6)
(7) Resistance of copper wire
At this point we are able to calculate the ratio of the resistance of both wires:
(8)
(9)
Finally:
This is the ratio
Acceleration is change in velocity over change in time. Your Δv is +13.9, since you increased speed by 50 km/h which is 13.9 m/s, and your Δt is 10s. 13.9/10 = 1.39 m/s^2, the standard units for acceleration. Make sense?
The voltage exists between the fence and the ground. The cow is grounded. The cow is touching the ground, completing the circuit of electricity. <span>When the cow comes into contact with the fence, it becomes an electric ground which sends an electric current into the cow, through the cow, and into the ground. The pain experienced from the shock is due to the current that flows through the cow.</span>
Answer:
a) 
b) 
Explanation:
a)
Given:
amount of heat transfer occurred,
initial temperature of car, 
final temperature of car, 
We know that the change in entropy is given by:

(heat is transferred into the system of car)

b)
amount of heat transfer form the system of house,
initial temperature of house, 
final temperature of house, 



Answer:
A, the energy an object has due to its motion.
Explanation:
Kinetic energy is the energy created by motion.