Answer:
u = 25 m/s
Explanation:
given,
length of skid = 93 m
coefficient of friction = 0.35
final velocity = 0 m/s
initial velocity = ?
force here is friction f = μ mg
F = ma
now com paring
-μ mg = m a
a = - μ g
a = - 0.35 x 9.8
a = -3.43 m/s²
we know,
v² = u² + 2 a s
0 = u² - 2 x 3.43 x 93
u² = 637.98
u = 25.26 m/s
u = 25 m/s (two significant figure)
Answer:
1) Q ’= 8 Q
, 2) q ’= 16 q
, 3) r ’= ¾ r
Explanation:
For this exercise we will use Coulomb's law
F = k q Q / r²
It asks us to calculate the change of any of the parameters so that the force is always F
Original values
q, Q, r
Scenario 1
q ’= 2q
r ’= 4r
F = k q ’Q’ / r’²
we substitute
F = k 2q Q ’/ (4r)²
F = k 2q Q '/ 16r²
we substitute the value of F
k q Q / r² = k q Q '/ 8r²
Q ’= 8 Q
Scenario 2
Q ’= Q
r ’= 4r
we substitute
F = k q ’Q / 16r²
k q Q / r² = k q’ Q / 16 r²
q ’= 16 q
Scenario 3
q ’= 3/2 q
Q ’= ⅜ Q
we substitute
k q Q r² = k (3/2 q) (⅜ Q) / r’²
r’² = 9/16 r²
r ’= ¾ r
Answer:
P₁ = 2.215 10⁷ Pa, F₁ = 4.3 106 N,
Explanation:
This problem of fluid mechanics let's start with the continuity equation to find the speed of water output
Q = A v
v = Q / A
The area of a circle is
A = π r² = π d² / 4
Let's look at the speeds at each point
v₁ = Q / A₁ = Q 4 /π d₁²
v₁ = 10 4 /π 0.5²
v₁ = 50.93 m / s
v₂ = Q / A₂
v₂ = 10 4 /π 0.25²
v₂ = 203.72 m / s
Now we can use Bernoulli's equation in the colon
P₁ + ½ ρ v₁² + ρ g y₁ = P₂ + ½ ρ v₂² + ρ g y₂
Since the tube is horizontal y₁ = y₂. The output pressure is P₂ = Patm = 1.013 10⁵ Pa, let's clear
P₁ = P2 + ½ rho (v₂² - v₁²)
P₁ = 1.013 10⁵ + ½ 1000 (203.72² - 50.93²)
P₁ = 1.013 10⁵ + 2.205 10⁷
P₁ = 2.215 10⁷ Pa
la definicion de presion es
P₁ = F₁/A₁
F₁ = P₁ A₁
F₁ = 2.215 10⁷ pi d₁²/4
F₁ = 2.215 10⁷ pi 0.5²/4
F₁ = 4.3 106 N
Answer:
The entropy of a gas increases when it expands into a vacuum because the number of possible states increases .
Explanation:
When a gas expand in a vacuum, the molecules of the gases vibrates very fast and starting moving with higher velocity in random directions which means the level of disorder in the gases increases.
Now the possible state of the gas molecule increases such as the particle can be located at different position due to increased randomness.
<u>Entropy is the measure of this randomness and thus with this increased randomness entropy also increases.</u>
Answer:
Humus
Explanation:
Its Humus I believe. I remember learning something like this.