The potential energy, E, of the penny is given by E=mgh. The energy, Q, required to raise the temperature of an object by an amount ΔT is given by Q=mcΔT. We can equate these two to get the result but we must use proper units and include the 60%:
(0.6)mgh=mcΔT
We see we can divide out the mass from each side
0.6gh=cΔT, then 0.6gh/c=ΔT
(0.6)9.81(m/s²)50m/385(J/kg°C) = 0.7644°C
since this is the change in temperature and it started at 25°C we get
T=25.7644°C
As you can see the result does not depend on mass. The more massive the copper object the more potential energy it will have to contribute to the heat energy, but the more stuff there will be to heat up, and the effect is that the mass cancels.
Answer:
It's false.... correct is a2+2ab+b2
Step-by-step explanation:
This cannot be factored anymore although. when we try to substitute a with 5 and b with 2, the answer in the right hand side of the equation is -9.
That's why it's false.
The best correct answer is option E. If two or more polygons are congruent, then rigid transformations can be used to map one polygon onto the other. <span>Two figures are said to be congruent when they have the same shape and
size or if one object is a mirror image of the other object.</span>
The first thing we are going to assume for this case is that the tree and the post are located in the same place.
From that place, both cast a shadow in the same direction.
We then have two similar triangles.
Therefore, we have the following relationship:
From here, we clear the value of x.
We have then:
Rewriting:
Answer:
the tree is 30 feet tall
