Answer:
1) p₀ = 45000 N / s
, p₀ '= 1800
, b) I = -45000 N s
, I = 1800 Ns
Explanation:
Impulse equals the change in momentum
I = Δp
1) the initial moment of the car
p₀ = M v
p₀ = 1500 30
p₀ = 45000 N / s
the change at the moment is
Δp = 45000
because the end the car is stopped
moment of the person
P₀ ’= m v
p₀ '= 60 30
p₀ '= 1800
D₀ '= 1800
2) of the momentum change impulse ratio
car
I = Δp
I = -45000 N s
person
I = Δpo '
I = 1800 Ns
3) the object that give the momentum to stop the wall motoring
The person is stopped by the impulse given by the car
a) This area is the one that absorbs most of the vehicle impulse
be) If using a safety painter, the time during which the greater force will act, therefore the lessons decrease
c) The air bag helps reduction in the speed of the person relatively quickly.
Answer:Convection
Explanation:
Convection is the heat transfer procedure by the movement of liquid or gas molecules. It is a combination of diffusion and bulk motion of molecules. Near the surface of the liquid diffusion process dominates while at certain height bulk motion of liquid dominates.
Convection can be
Natural : Natural convection occurs due to density differences
Forced: Force convection occurs when we apply external heat source.
Answer:
a = 64 ft / s²
Explanation:
The force in a spring is given by Hooke's law
F = -k x
Let's use the initial data to calculate the spring constant
k = F / x
Reduscate to the English system
x = 3 in (1foot/12 in) =0.25 foot
k = 0.3 / 0.25
k = 1.2 lb / foot
Now we can use Newton's second law
F = ma
a = F / m
a = -k x / m
m = w / g
m = 0.3 / 32 = 0.009375
x= 6 in (1foot /12 in)= 0.5 foot
a = - 1.2 0.5 / 0.009375
a = 64 ft / s²
