To solve this problem we will use the basic concept given by the Volume of a sphere with which the atom approaches. The fraction in percentage terms would be given by the division of the total volume of the nucleus by that of the volume of the atom, that is,
Therefore the percent of the atom's volume is occupied by mass is 
<span>A physical change is any change that alters the form or appearance of a substance but does not change it into another substance
-Some of the physical properties may be altered, but the chemical composition stays the same
-Examples: Bending, Crushing, Cutting, Melting, Freezing, Boiling</span>
Answer:
Machines reduce the time of work hence reducing the rate of doing work ( power ).
Machines e.g pulleys carry heavy loads with a less and reasonable effort.
Machines e.g generators induce current in a limited amount of time
Answer:
66.8°C
Explanation:
dQ = m*cp*dT where:
m = mass of block
cp = specific heat of iron
dT = temperature change
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dQ = 3.5 10^4 J
cp = 0.45 Kj / Kg = 450 J / Kg
3.5 10^4 = 2.3 * 450 * dt-----dt = 35000 / 450 * 2.3 = 33.8 °
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Final temperature = 33 + 33.8 = 66.8 °C
