Answer:
turning lights of when you aren't using them
Explanation:
When there is no change in chemical composition of a substance then it is known as physical change.
When we say that mass is conserved during a physical change then it means that total mass of the substance or object will remain the same from beginning till the end.
For example, a metal box of mass 20 grams is beaten with hammer. Its shape will change which is a physical change and after beaten with the hammer its mass still remains 20 grams.
Answer:
C. both a speed and a direction
Answer:
Avogadro's law.
Explanation:
Avogadro’s law states that, equal volumes of all gases at the same temperature and pressure contain the same number of molecules.
Mathematically,
V n
V = Kn where V = volume in cm3, dm3, ml or L; n = number of moles of gas;
K = mathematical constant.
The ideal gas equation is a combination of Boyle's law, Charles' law and Avogadro’s law.
V 1/P at constant temperature (Boyle’s law)
V T at constant pressure ( Charles’law)
V n at constant temperature and pressure ( Avogadro’s law )
Combining the equations yields,
V nT/P
Introducing a constant,
V = nRT/P
PV = nRT
Where P = pressure in atm, Pa, torr, mmHg or Nm-2; V = volume in cm3, dm3, ml or L; T = temperature in Kelvin; n = number of moles of gas in mol; R = molar gas constant = 0.082 dm3atmK-1mol-1
The weight of an object is taken to be the force on the object due to gravity. The weight ( W ) is the product of the mass ( m ) of the object and the magnitude of the gravitational acceleration ( g ).
On Earth: g = 9.81 m/s²
m = 20 kg
W = m · g = 20 kg · 9.81 m/s² = 196.2 N
