A) lithium and beryllium
Explanation:
From the given row on the periodic table, only lithium and beryllium will conduct electricity.
What makes a substance able to conduct electricity?
- The presence of free mobile electrons and in some, ions allows them to carry electric currents.
Metals are generally known to be good conductors of heat and electricity. This is because, metals have a large pool of electrons i.e free mobile electrons. They are electropositive with a large size and readily release their electrons for conduction.
Lithium and Beryllium are in the metallic block on the periodic table.
Learn more:
Metals brainly.com/question/2474874
#learnwithBrainly
Answer:
trying to push a rock that never moves
Explanation:
Answer:
The plane would need to travel at least (.)
The runway should be sufficient.
Explanation:
Convert unit of the the take-off velocity of this plane to :
.
Initial velocity of the plane: .
Take-off velocity of the plane .
Let denote the distance that the plane travelled along the runway. Since acceleration is constant but unknown, make use of the SUVAT equation .
Notice that this equation does not require the value of acceleration. Rather, this equation make use of the fact that the distance travelled (under constant acceleration) is equal to duration times average velocity .
The distance that the plane need to cover would be:
.
As we know that acceleration is directly proportional to force, therefore as the force is doubled, acceleration gets doubled too.