Answer:
b. during the final stages of cooling, a lava flow contracts, forming tall polygonal fractures
Explanation:
The columnar joints are very interesting and attractive for the eye geological features. They are not very common feature which makes them even more interesting. Some of them have been covered by sediments so they are hidden below the surface, but some have remained above the surface, sticking out as the erosion acts much slower on them than the surrounding area. They form when the lava cools off very quickly at its final stages, thus starting to contract, and instead of being smooth, they become polygonal fractures that are very tall.
The combined momentum of the passengers is 5000 kgm/s.
<h3>Combined momentum of the passenger</h3>
The combined momentum of the passengers is calculated as follows;
P = mv1 + mv2
where;
- m is mass of the passengers
- v1 is velocity of the first passenger
- v2 is velocity of the second passenger
P = m(v1 + v2)
P = 5000(-1 + 2)
P = 5000 kgm/s
Thus, the combined momentum of the passengers is 5000 kgm/s.
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Answer:
L = 1.545 m
Explanation:
Let the total length of the rod is L
now the torque must applied on the other end of the rod so that it will balance the torque due to weight of rock on other side of fulcrum
so we will have

so we have

F = 663 N


The greenhouse effect is a warming effect caused by certain gases that retain heat from sunlight. Without such gases, the average surface temperature of the Earth would be below freezing, and as explained by the Encyclopedia of Environmental Science, “life, as we know it, would not exist.”
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The global warming debate is centered upon whether added greenhouse gases released by human activity will overheat the Earth and cause harmful effects.</span><span>
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The centripetal force, Fc, is calculated through the equation,
Fc = mv²/r
where m is the mass,v is the velocity, and r is the radius.
Substituting the known values,
Fc = (112 kg)(8.9 m/s)² / (15.5 m)
= 572.36 N
Therefore, the centripetal force of the bicyclist is approximately 572.36 N.