Electromagnets have certain advantages over permanent magnets. One of the major advantage is, the amount of electric current can easily be controlled, in turn, magnetic field can be controlled. Out of all the options, option D would be the best answer.
In short, Your Answer would be option D) Electromagnets can easily be turned on and off.
Hope this helps!
D. Weathering
The six steps of the rock cycle includes Weathering and Erosion, Transportation, Deposition, Compaction and Cementation. Metamorphism, Rock Melting.
Deposition is the process where rock particles sink at the rivers and become sediment.
Weathering is the process by which wind and water breaks down igneous, sedimentary, and metamorphic rocks. The process refers to large rocks broken down into smaller pieces and the broken off particles stay in the area.
Answer:
Explanation:
Theoretical efficiency = T₁ - T₂ / T₁ where T₁ and T₂ is absolute temperature of hot and cold end of the heat engine.
= 600 / (273 + 700 )
= 600 / 973
= .6166
operating efficiency = 40% of .6166
= .4 x .6166
= .2466 = 24.66 %
efficiency = work output / heat input
= 5000 / heat input = .2466
heat input = 5000 / .2466
= 20275.75 J .
HEAT EXTRACED = 20275.75 J.
Answer:
Explanation:
Hello! To solve this problem we must be clear about the concept of energy conservation, and kinetic energy with the following sentence
The kinetic energy of the two cars (v = 1.2m / S) plus the kinetic energy of the third car (v = 3.5m / S) must be equal to the kinetic energy of the three cars together.
The kinetic energy is calculated by the following equation.

m= mass of the cars=26500kg
V=speed
E=kinetic energy
taking into account the above, the following equation is inferred
1= the cars are separated
2=
the cars are togheter
E1=E2

where
m= mass of each car
V1= 1.2m/s
Va=3.5,m/S

m= mass of each car
V=speed (in m/s) of the three coupled cars after the first couples with the other two
Solving



the speed of the three coupled cars after the first couples with the other two is 2.245m/s
Answer:
Heavier person
Explanation:
Work = force × distance. In this case, force = weight and distance = height of the stairs. For both people, the height of the stairs is the same. Since the heavier person has more weight, they did more work.