Answer:
Most metals are in the liquid state at room temperature.<u>False</u><u>.</u>
Explanation:
it needs excess heat except mercury and lithium.
The correct answer to the question is A) Electrons.
EXPLANATION:
The electrical conductivity of a metal or any substance depends on the free electron concentration of the metals.
Free electrons are those electrons which are present in the conduction band of the metals. These electrons experience less amount of force attraction from the nucleus. Protons and neutrons do not contribute anything to the current conduction in a metal.These sub atomic particles are bound to the nuclei of atoms.
When we maintain potential difference across the two ends of a conductor, the free electrons are drifted towards the positive terminal of the battery.
Hence, electrical conductivity of a substance is the ability of the electrons to move inside the substance.
More is the conductivity of the substance, the lesser is the resistance to the flow of electrons inside the substance, and vice versa.
Answer:
Orbital period, T = 1.00074 years
Explanation:
It is given that,
Orbital radius of a solar system planet, 
The orbital period of the planet can be calculated using third law of Kepler's. It is as follows :
M is the mass of the sun
T = 31559467.6761 s
T = 1.00074 years
So, a solar-system planet that has an orbital radius of 4 AU would have an orbital period of about 1.00074 years.
Terminal speed is the maximum speed that a falling object can reach and is based on aerodynamic resistance. In a vacuum, an object falling toward a planet as a result of gravity will continue to accelerate until it hits the ground.
However, if the object is falling through an atmosphere, such as on earth, then it will accelerate up to the point that the aerodynamic resistance cancels the downward force due to gravity, and it travels at a constant maximum speed, called the terminal velocity. At this point, resistance is equal to acceleration due to gravity. At terminal velocity, the skydiver's acceleration is zero.
Answer:
0.056 miles away
Explanation:
From sound wave,
v = 2x/t .................................. Equation 1
Where v = velocity of sound in air, x = distance of echo, t = time.
making x the subject of the equation,
x = 2v/t........................... Equation 2.
Given: v = 344 m/s, t = 7.6 s.
Substituting into equation 2
x = 2(344)/7.6
x = 90.53 m.
x = 90.53/1609.344
x = 0.056 mile.
Thus the lighting strike 0.056 miles away
