<h2>Answers:</h2><h2 /><h2>a) Arrow B</h2><h2>b) Arrow E</h2>
Explanation:
Refraction is a phenomenon in which a wave (the light in this case) bends or changes its direction <u>when passing through a medium with a refractive index different from the other medium.</u> Where the Refractive index is a number that describes how fast light propagates through a medium or material.
According to this, if we observe the rays A an D passing throgh the biconcave lens, we will have two mediums:
1) The air
2)The material of the biconcave lens
This two mediums have different refractive indexes, hence the rays will change the direction.
-For the incident ray A, the corresponding refractive ray is B, because is the ray that bends after passing throgh the lens
-For the incident ray D, the refracted ray is E following the same principle.
Answer:
Answer:
3 g/cm
Explanation:
Mass of stone = 30 g
Initial volume of cylinder = 50 cm
Increased volume = 60 cm
Volume = 60-50
= 10 cm
Density of stone = Mass/Volume
= 30/10
= 3 g/ml as 1 ml = 1 cm
= 3 g/ml
Explanation:
Answer:
b) 20 kJ
Explanation:
Efficiency of carnot engine = (T₁ - T₂ ) / T₁ Where T₁ is temperature of hot source and T₂ is temperature of sink .
T₁ = 270 + 273 = 543K
T₂ = 50 + 273 = 323 K
Putting the given values of temperatures
efficiency = (543 - 323) / 543
= .405
heat input = 50 KJ
efficiency = output work / input heat energy
.405 = output work / 50
output work = 20.25 KJ.
= 20 KJ .
Answer:
Q = 2.95*10^5 kJ
Explanation:
In order to calculate the energy required to melt the cooper, you first calculate the energy required to reach the boiling temperature. You use the following formula:
(1)
m: mass of cooper = 540 kg
c: specific heat of cooper = 390 J/kg°C
Tb: boiling temperature of cooper = 1080°C
T1: initial temperature of cooper = 20°C
You replace the values of the parameters in the equation (1):
Next, you calculate the energy required to melt the cooper by using the following formula:
(2)
Lf: melting constant of cooper = 134000J/kg
Finally, the total amount of energy required to melt the cooper from a temperature of 20°C is the sum of Q1 and Q2:
The total energy required is 2.95*10^5 kJ
