Answer:
α = 0
, w = w₀
Explanation:
Torque is related to angular acceleration by Newton's second law for rotational motion.
τ = I α
Where τ is the torque, I the moment of inertia and α the angular acceleration.
If we apply an external torque for the sum of all torques to be zero, the angular acceleration must fall to zero
α = 0
Since the acceleration is zero, the angular velocity you have at that time is constantly killed.
w = w₀ + α t
w = w₀ + 0
Answer:
2 Joules
Explanation:
Kinetic Energy = 1/2 of (Mass x Velocity^2)
Before swinging, T has only potential energy, (no speed)
Ui = mgh
Where h is the vertical displacement of T
From the laws of geometry,
cos45 = (L-h)/L
cos45 = 1-h/L
h/L = 1-cos45
h = L(1-cos45)
Therefore
Ui = mgL(1-cos45)
Proceeding the same way,
Twill raise to aheight of h' due to swing
h' = L(1-cos30)
The PE of T after swing is
Uf = mgh'
Uf = mgL(1-cos30)
Along with the PE , T has some kinetic energy results due to the moment.
Tf = 0.5*mv^2
According to the law of conservation of energy,
Ui = Uf+Tf
mgL(1-cos45) = mgL(1-cos30) + 0.5*mv^2
gL(co30-cos45) = 0.5*v^2
9.8*20*(co30-cos45) = 0.5*V^2
v = 7.89 m/s
<span>The speed f T after swing is 7.89 m/s</span>
Friction-reducing technologies used in the Variable Compression Turbo Engine are Diamond-like coating on valve lifters, micro finishing on crankshaft and camshaft and mirror bore coating on cylinder wall.
<u>Explanation:</u>
Variable compression is a technology to adjust the compression of an internal combustion engine while the engine is in operation. At this time friction may occur that need to be reduced. To reduce this friction some technologies are used like
- Diamond-like coating on valve lifters
- Micro finishing on crankshaft and camshaft
- Mirror bore coating on cylinder wall
A hydrogen free diamond like carbon coating is applied to an engine valve lifter to reduce mechanical loss. Micro finishing on crankshaft and camshaft achieves improvement in geometric parameters such as roundness. Mirror bore coating on cylinder wall raises energy efficiency by reducing the friction inside the engine.
