Answer:
40sec
Explanation:
Data
Work = 440 J
Power= 11watt
time = ?
Power = work done/time
===> time = work done/power
= 440/11
= 40sec
206Pb = 1.342 x10^22 atoms
<span>To find the number of atoms, you must first find the number of moles. If 238U is 238.029g/mol, and we have 1.75 grams, how many moles is that? 1.75 divided by 238.029 = 0.007352045 moles. To find the number of atoms in 0.007352045 moles, you multiply by a mole: </span>
<span>0.007352045 x 6.02 x 10^23 = 4.426 x10^21 atoms. </span>
<span>Same procedure for 206Pb: </span>
<span>4.59 divided by 205.97446 = 0.022284316 moles </span>
<span>0.022284316 x 6.02 x 10^23 = 1.342 x10^22 atoms. </span>
<span>Hope that helps you!
https://answers.yahoo.com/question/index?qid=20100331153014AAoMXcu
</span>
Answer:
Some lenses are used to focus light to a pre-defined point based on the amount of curvature of their surfaces.
In a piano design convex, some surfaces are flat while others has positive lenses (biconvex)
Explanation:
Solution
These lenses are applied to pay attention to light in a point pre-defined based on the amount of curvature of their surfaces.
For that of a plano-convex design, one surface has a positive curve and for biconvex lenses, both surfaces are positively curved while the other remains flat.
when used practically, plano-convex lenses are most commonly used where the object being imaged is far apart from lens.
What are your answer choices?
The velocity of the object is zero (the object is at rest)
Explanation:
A position vs time graph represents the motion of an object; in particular:
- The position of the object x(t) is represented on the y-axis
- The time t is represented on the x-axis
For a position-time graph, the slope of the graph is given by

where
is the change in position
is the change in time
However, we see that this is equivalent to the definition of velocity:

Therefore, the slope of a position-time graph is equivalent to the velocity of the object.
And so, a horizontal segment on a position vs time graph means that the object has zero velocity (because the slope is zero).
Learn more about velocity:
brainly.com/question/5248528
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