Look at the third one i think its the answer
What question are you asking?
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:
r₁/r₂ = 1/2 = 0.5
Explanation:
The resistance of a wire is given by the following formula:
R = ρL/A
where,
R = Resistance of wire
ρ = resistivity of the material of wire
L = Length of wire
A = Cross-sectional area of wire = πr²
r = radius of wire
Therefore,
R = ρL/πr²
<u>FOR WIRE A</u>:
R₁ = ρ₁L₁/πr₁² -------- equation 1
<u>FOR WIRE B</u>:
R₂ = ρ₂L₂/πr₂² -------- equation 2
It is given that resistance of wire A is four times greater than the resistance of wire B.
R₁ = 4 R₂
using values from equation 1 and equation 2:
ρ₁L₁/πr₁² = 4ρ₂L₂/πr₂²
since, the material and length of both wires are same.
ρ₁ = ρ₂ = ρ
L₁ = L₂ = L
Therefore,
ρL/πr₁² = 4ρL/πr₂²
1/r₁² = 4/r₂²
r₁²/r₂² = 1/4
taking square root on both sides:
<u>r₁/r₂ = 1/2 = 0.5</u>
Answer:
(a) 10 s
(b) 30 m/s
(c) 150 m
Explanation:
The motorist's position at time t is:
x = 15t
The officer's position at time t is:
x = ½ (3) t² = 1.5 t²
(a) When they have the same position, the time is:
15t = 1.5 t²
t = 0 or 10 s
(b) The officer's speed is:
v = 3t
v = 30 m/s
(c) The position is:
x = 15t = 150 m
