(9) Mechanical advantage = force by machine / force applied to machine
0.6 = 600 / F
F = 1000 N
(2) Efficiency = (output / input) x 100
Efficiency = (500 / 2000) x 100
Efficiency = 25%
(4) The overall energy conversion in power plants is chemical to electrical while in dams it is potential to electrical.
(5) Using the formula:
1568 = 40 x 9.81 x h
h = 4.0 m
(6) Potential to electrical
(10) An object raised and held stationary above the ground.
Answer:
energy is released in the reaction.
Explanation:
Answer:
Atomic number = 10
Mass number = 20
Explanation:
Mass number = neutrons+protons
Mass number = 10+10 = 20
Answer:
Al 72.61%
Mg 27.39%
Explanation:
To obtain the mass percentages, we need to place the individual masses over the total mass and multiply by 100%.
If we observe clearly, we can see that the parameters given are the moles. We need to convert the moles to mass.
To do this ,we need to multiply the moles by the atomic masses. The atomic mass of aluminum is 27 while that of magnesium is 24.
Now, the mass of aluminum is thus = 27 * 0.0898 = 2.4246g
The mass of magnesium is 0.0381 * 24 = 0.9144g
We can now calculate the mass percentage.
The total mass is 0.9144 + 2.4246 = 3.339g
% mass of Al = 2.4246/3.339 * 100 = 72.61%
% mass of Mg = 0.9144/3.39 * 100 = 27.39%
