Answer: Dust released in the air could be radioactive.
Explanation:
Uranium is a radioactive element. It decays naturally to attain stability. While mining, the dust displaces into the air causing not only harm to environment but for the workers as well. The released in the air could be radioactive which would be inhaled posing threat for lung cancer.
Thus, the correct answer is dust released in the air could be radioactive is a concern about mining Uranium.
Answer:
The change in entropy ΔS = 0.0011 kJ/(kg·K)
Explanation:
The given information are;
The mass of water at 20.0°C = 1.0 kg
The mass of water at 80.0°C = 2.0 kg
The heat content per kg of each of the mass of water is given as follows;
The heat content of the mass of water at 20.0°C = h₁ = 83.92 KJ/kg
The heat content of the mass of water at 80.0°C = h₂ = 334.949 KJ/kg
Therefore, the total heat of the the two bodies = 83.92 + 2*334.949 = 753.818 kJ/kg
The heat energy of the mixture =
1 × 4200 × (T - 20) = 2 × 4200 × (80 - T)
∴ T = 60°C
The heat content, of the water at 60° = 251.154 kJ/kg
Therefore, the heat content of water in the 3 kg of the mixture = 3 × 251.154 = 753.462
The change in entropy ΔS = ΔH/T = (753.818 - 753.462)/(60 + 273.15) = 0.0011 kJ/(kg·K).
F(of spring)=230x=ma=3.5(5)=17.5=230x; x=0.07m.
Its C because the circuit is connected with battery and light bulb.
Given:
Shaft Power, P = 7.46 kW = 7460 W
Speed, N = 1200 rpm
Shearing stress of shaft, 
= 30 MPa
Shearing stress of key, 
= 240 MPa
width of key, w = 
d is shaft diameter
Solution:
Torque, T = 
where,
= 59.365 N-m
Now,
d = 0.0216 m
Now,
w = = 
= 5.4 mm
Now, for shear stress in key
= 
we know that
T = 
= F. 
⇒ = 
⇒ 
= 
length of the rectangular key, l = 4.078 mm
