<span>The amount of heat energy needed to increase the temperature of a substance by </span>
<span> is given by:
</span>
<span>
where m is the mass of the substance, Cs is its specific heat capacity and </span>
<span> is the increase in temperature of the substance.
In this problem, we have a certain mass m of gold, with specific heat capacity </span>
<span>, to which we add Q=2825 J of energy. Its temperature increases by </span>
<span>. Therefore, if we re-arrange the previous equation, we can find the mass of the block of gold:
</span>
<span>
So, the correct answer is B.</span>
Any key words? That they put there
Answer:
<em>The tourist's average speed was 80 mph</em>
Explanation:
<u>Average Speed
</u>
If an object travels a distance d in a time t regardless of the direction, the average speed is the quotient of the distance over the time:
The tourist leaves Pittsburgh and travels 60 miles South in 45 minutes. Then he heads West and travels 100 miles in 1 hour and 15 minutes.
The total distance traveled is:
d = 60 miles + 100 miles = 160 miles
The total time is:
t = 45 minutes + 1 hour + 15 minutes = 2 hours
The average speed is:
v = 80 mph
The tourist's average speed was 80 mph
Answer:
I₂ = 25.4 W
Explanation:
Polarization problems can be solved with the malus law
I = I₀ cos² θ
Let's apply this formula to find the intendant intensity (Gone)
Second and third polarizer, at an angle between them is
θ₂ = 68.0-22.2 = 45.8º
I = I₂ cos² θ₂
I₂ = I / cos₂ θ₂
I₂ = 75.5 / cos² 45.8
I₂ = 155.3 W
We repeat for First and second polarizer
I₂ = I₁ cos² θ₁
I₁ = I₂ / cos² θ₁
I₁ = 155.3 / cos² 22.2
I₁ = 181.2 W
Now we analyze the first polarizer with the incident light is not polarized only half of the light for the first polarized
I₁ = I₀ / 2
I₀ = 2 I₁
I₀ = 2 181.2
I₀ = 362.4 W
Now we remove the second polarizer the intensity that reaches the third polarizer is
I₁ = 181.2 W
The intensity at the exit is
I₂ = I₁ cos² θ₂
I₂ = 181.2 cos² 68.0
I₂ = 25.4 W
