Answer:
a. one-half as great
Explanation:
The power developed by the first lifter is one-half as great as that of the second person.
Power is defined as the rate at which work is done;
Power =
Since the two lifters do the same work at different time, let us estimate their power;
P₁ = P₂ =
We see that for P₁, power is half of the work done whereas in P₂ power is the same as the work done.
Therefore,
The power of the first weight lifter is one-half the second lifter.
Time = (distance) / (speed)
= (30 km) / (30 m/s)
= (30,000 m) / (30 m/s)
= (30,000 / 30) sec
= 1,000 seconds
= 16 minutes 40 seconds
Answer:
17.6 N
Explanation:
The force exerted by the punter on the football is equal to the rate of change of momentum of the football:
where
is the change in momentum of the football
is the time elapsed
The change in momentum can be written as
where
m = 0.55 kg is the mass of the football
u = 0 is the initial velocity (the ball starts from rest)
v = 8.0 m/s is the final velocity
Combining the two equations and substituting the values, we find the force exerted on the ball:
The missing word here is <u>Asthenosphere.</u><u> </u>
The convection in the asthenosphere directly propels the tectonic plates of the earth.
Did you know that the asthenosphere is thought to remain malleable because of heat from deep within the Earth? It is thought to be lubricating the earth's tectonic plates' undersides and enabling movement.
The older, denser portions of the lithosphere that are dragged downward in subduction zones are stored in the asthenosphere, according to the theory of plate tectonics.
The lithosphere above is stressed by convection currents, and the cracking that frequently results manifests as earthquakes.
Magma is forced upward through volcanic vents and spreading centers by convection currents produced within the asthenosphere, which also results in the formation of new crust.
Learn why properties of the asthenosphere are important: brainly.com/question/11484043
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