Because a Btu is so small, energy is usually measured in millions of Btus. 1 Btu = the amount of energy required to increase the temperature of one pound of water (which is equivalent to one pint) by one degree Fahrenheit. This is roughly the heat produced from burning one match.
<em>https://www.ucsusa.org/clean_energy/our-energy-choices/how-is-energy-measured.html</em>
Answer:
= 1.75 × 10⁻⁴ m/s
Explanation:
Given:
Density of copper, ρ = 8.93 g/cm³
mass, M = 63.5 g/mol
Radius of wire = 0.625 mm
Current, I = 3A
Area of the wire,
=
Now,
The current density, J is given as
= 2444619.925 A/mm²
now, the electron density, 
where,
=Avogadro's Number

Now,
the drift velocity, 

where,
e = charge on electron = 1.6 × 10⁻¹⁹ C
thus,
= 1.75 × 10⁻⁴ m/s
A motor is built to use all those things and produce mechanical energy.
Answer:
satellite B
Explanation:
A .F= G (mM)/r²
B .F= G (2mM)/r² = 2G (Mm)r²
C .F= G (3mM)/(2r)² = ¾G (mM)/r²
D .F= G (4mM)/(2r)² = G (mM)/r²