Answer:
τ = 132.773 lb/in² = 132.773 psi
Explanation:
b = 12 in
F = 60 lb
D = 3.90 in (outer diameter) ⇒ R = D/2 = 3.90 in/2 = 1.95 in
d = 3.65 in (inner diameter) ⇒ r = d/2 = 3.65 in/2 = 1.825 in
We can see the pic shown in order to understand the question.
Then we get
Mt = b*F*Sin 30°
⇒ Mt = 12 in*60 lb*(0.5) = 360 lb-in
Now we find ωt as follows
ωt = π*(R⁴ - r⁴)/(2R)
⇒ ωt = π*((1.95 in)⁴ - (1.825 in)⁴)/(2*1.95 in)
⇒ ωt = 2.7114 in³
then the principal stresses in the pipe at point A is
τ = Mt/ωt ⇒ τ = (360 lb-in)/(2.7114 in³)
⇒ τ = 132.773 lb/in² = 132.773 psi
Even with no friction, it depends on the slope of the roof. That is, it depends on how much elevation (altitude) he loses during the slide.
Whatever that number is ... call it 'h' ... Santa's speed when he reaches the edge is
Square root of (19.6h) meters per second.
It doesn't matter how much he weighs, or how far he has slud. Only how much altitude he lost on the slope while sliding.
The answer is A, because it’s the first one
Answer:
Speed of the airplane 10.0 s later = 12.2 m/s
Explanation:
Mass of Boeing 777 aircraft = 300,000 kg
Braking force = 445,000 N
Deceleration

Initial velocity, u = 27 m/s
Time , t = 10 s
We have equation of motion, v =u +at
v = 27 + (-1.48) x 10 = 27 - 14.8 = 12.2 m/s
Speed of the airplane 10.0 s later = 12.2 m/s