Answer:
W=16.58J
Explanation:
initial information we have
work: 
stretched distance: 
from this, we can find the value of the constant of the spring k, with the equation for work in a spring:

substituting known values:

and clearing for k:

and now we want to know how much work is done when we stretch the spring a distance of 6.5cm from equilibrium, so now x is:

and using the same formula for work, with the value of k that we just found:


Answer:
Yes, the car driver is exceeding the given limit.
Explanation:
<u>Given:</u>
- Speed of the car, v = 38.0 m/s.
- Speed limit of the highway,

<h2><u>
Converting the speed limit from mi/h to m/s:</u></h2>
We know,
1 mi = 1.60934 km.
1 km = 1000 m.
Therefore, 1 mi = 1.60934 × 1000 m = 1609.34 m.
1 hour = 60 minutes.
1 minute = 60 seconds.
Therefore, 1 hour = 60 × 60 seconds = 3600 seconds.
Using these values,

Therefore,

Clearly,

which means, the car driver is exceeding the given speed limit.
Answer:
Combination or synthesis
Explanation:
The reaction is a combination or synthesis reaction in which two or more substances combines to give a single product.
In such a reaction there is formation of compounds from the union of their constituent elements.
The driving force for such reactions is the large and negative heat of formation of the product.
So, this is a combination reaction.
Scientists use theories to explain these things
Explanation:
An electrified comb is charged comb ( let say by running it through the hair) and when it is brought in the proximity of pieces of paper, the pieces tend to cling to it. This happens because the charged comb induces an opposite charge in the paper pieces and as opposite charges attract each other, the pieces are clinged.