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Lead has a density of 11.35g/cm'3. a lead ball weighs about 2kg. what is the radius of this ball

User Sykora
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1 Answer

8 votes

Answer:

The radius of the ball is 3.48 cm

Explanation:

Density

The density of a substance is the mass per unit volume. The density varies with temperature and pressure.

The formula to calculate the density of a substance of mass (m) and volume (V) is:


\displaystyle \rho=(m)/(V)

The density of lead is \rho=11.35\ g/cm^3 and the mass of a ball of lead is m=2 kg=2,000 g. We can calculate the volume by solving for V:


\displaystyle V=(m)/(\rho)


\displaystyle V=(2000\ g)/(11.35\ g/cm^3)


V=176.2115\ cm^3

Since the shape of the object is a sphere, and the volume of a sphere of radius r is:


\displaystyle V=(4)/(3)\cdot \pi\cdot r^3

We can solve for r and obtain:


\displaystyle r=\sqrt[3]{(3V)/(4\pi)}

Substituting:


\displaystyle r=\sqrt[3]{(3*176.2115)/(4\pi)}


\displaystyle r=\sqrt[3]{42.0674}


\boxed{r=3.48\ cm}

The radius of the ball is 3.48 cm

User Luisenrique
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