Hydrogen (H) has a molar mass of about 1.007 g/mol and has 1 electron.
Oxygen (O) has a molar mass of about 15.999 g/mol and has 8 electrons.
Then water (H₂O) has a total molar mass of about 18.015 g/mol and has 10 electrons.
30 g of water is the mass of
(30 g) × (1/18.015 mol/g) ≈ 1.66528 mol
of water. Recall that 1 mole is around 6.022 × 10²³ molecules (i.e. Avogadro's number). So 30 g of water is the mass of approximately 1.00285 × 10²⁴ molecules of water.
If each molecule contains 10 electrons, then 30 g of water contains 1.00285 × 10²⁵ ≈ 10²⁵ electrons.
The acceleration due to gravity is not due to the Earth's motion through space. It is due to the gravitational force pulling you towards the center of mass of the Earth. The ground pushes back<span>, and what you </span>feel<span> is </span>your<span> weight. This is the same as what you </span>feel<span> in an accelerating </span>car<span>.</span>
Answer:
Vf = - 20 m/s ( -ve sign shows that the particle is moving opposite to positive x- direction).
Explanation:
Given:
Vi = 20 m/s, m= 10 mg =1 × 10⁻⁵ kg, q= -4.0 × 10⁻⁶ C , E= 20 N/C. t= 5.0 s
first to find Electric Force
F= Eq = 20 × -4.0 10⁻⁶ C = - 8 × 10⁻⁵ N (-ve sign shows that the field will push the particle opposite to positive x- direction)
We also have F=ma
⇒ a = F/m = - 8 × 10⁻⁵ N / 10 × 10⁻⁵ kg = -8 m/s² ( -ve sign shows that the particle is accelerated opposite to positive x- direction)
Now according the first equation of Motion.
Vf = Vi + at
Vf = 20 m/s + -8 m/s² × 5 s
Vf= -20 m/s ( -ve sign shows that the particle is moving opposite to positive x- direction)
Answer:
C and E...................