Answer:
(a) v = 65.35 m/s
(b) ac = 82.16 m/s²
Explanation:
Kinematic of the blades of the wind turbine
The blades of the wind turbine describe circular motion and the formulas that apply to this movement are as follows:
v = ω * R Formula (1)
Where:
v : tangential velocity (m/s)
ω : angular velocity (rad/s)
R : radius of the particle path (m)
The velocity vector is tangent at each point to the trajectory and its direction is that of movement. This implies that the movement has centripetal acceleration (ac):
ac = ω²* R Formula (1)
ac : centripetal acceleration (m/s²)
Data:
ω= 12 rpm = 12 rev/min
1 rev = 2π rad
1 min = 60 s
ω= 12 rev/min = 12 (2π rad)/(60 s)
ω = 1.257 rad/s
R = 52 m
(a)Tangential velocity at the tip of a blade (v)
We apply the formula (1)
v = ω* R
v = ( 1.257)* (52) = 65.35 m/s
(a) Centripetal acceleration at the tip of a blade (ac)
We apply the formula (2)
ac = ω²*R
ac = ( 1.257)²* (52) = 82.16 m/s²
Answer:
The amount of Work done during the process = 0.01026 BTU
Explanation:
Initial Pressure (
) = 60 
Initial volume ( 
)= 1.78 
Final Pressure (
) = 20
Final Volume ( 
) = We have to calculate.
The relationship between pressure and volume during the process is = P 
⇒ × 
= × 
⇒ 
= ![[\frac{P_{1} }{P_{2}}]^{0.77} }](https://tex.z-dn.net/?f=%5B%5Cfrac%7BP_%7B1%7D%20%7D%7BP_%7B2%7D%7D%5D%5E%7B0.77%7D%20%20%7D)
⇒ = 
⇒ = 2.33
⇒ = 2.33 × 1.78
⇒ = 4.147 ------------ (1)
The work done during the process is given by W = 
Put all the values in the above formula we get
⇒ W = 
⇒ W = 79.54 lb f
We know that 1 lb f = 0.00129 BTU
⇒ W = 0.01026 BTU
This is the amount of Work done during the process in BTU
Answer:
The star's luminosity rises above its previous level. Because it is so cool, the surface will be red, and it will be much farther away from the center than it was during the earlier stages of star evolution. Despite its lower surface temperature, the red giant has a large surface area, which makes it very luminous.
Answer: There should be one brush on each slip ring.
Explanation:
A device that converts mechanical energy into electrical energy is known as an electric generator. The magnets are kept surrounding armature and axle. The armature rotates in between the magnets. This generates electric current which is detected by the ammeter.
It is based on Faraday's law - when a conductor moves in a magnetic field, an emf is induced in the conductor. Thus, a battery is not required. There should be one brush on each slip ring because the brushes must make contact with the rotating rings to supply current to the coil.
<h3>
Answer: B) his muscles</h3>
Explanation:
Specifically his leg muscles. As the leg muscles expand, they push down on the ground. Newton's 3rd law says that for any action, there's an opposite and equal reaction. That means a downward push into the ground will have the ground push back, more or less, and that's why the kangaroo will jump. The ground (and the earth entirely) being much more massive compared to the animal means that the ground doesn't move while the kangaroo does move. Perhaps on a very microscopic tiny level the ground/earth does move but it's so small that we practically consider it 0.
This experiment can be done with a wall as well. Go up to a wall and lean against it with your hands. Then do a pushup to move further away from the wall, but you don't necessarily need to lose contact with the wall's surface. As you push against the wall, the wall pushes back, and that causes you to move backward. If the wall was something flimsy like cardboard, then you could easily push the wall over and you wouldn't move back very much. It all depends how much mass is in the object you're pushing on.
