Question

1. a large piece of wood has a volume of 2.0m³ and a mass of 1200 kg. what is the density of this piece of wood?
2. a dry beaker has a mass of 55.0 g. when 50.0 ml of water is added to the beaker, the mass of the water and the beaker is 105.0 g. what is the density of the water?
3. a rectangular object is 15.0 cm long, 10.0 cm wide and 5.0 cm thick. the object has a mass of 450g.

a. what is the density of the object?
b. will the object float or sink in water? how do you know?

1. a bar of gold is 5.0 mm thick, 10.0 cm long and 2.0 cm wide. it has a mass of exactly mass value not given. what is the density of gold?
2. in your textbook, p.167, do the math - connect.

Explanation:

1.

Step1: Recall density formula

The formula for density is $D=\frac{m}{V}$, where $m$ is mass and $V$ is volume.

Step2: Substitute values

Given $m = 1200$ kg and $V=2.0$ m³, then $D=\frac{1200\ kg}{2.0\ m^{3}}$.

Step3: Calculate density

$D = 600$ kg/m³

Step1: Find mass of water

The mass of water $m$ is the total mass minus the mass of the dry beaker. So $m=105.0\ g - 55.0\ g=50.0\ g$.

Step2: Recall density formula

The formula for density is $D = \frac{m}{V}$, with $V = 50.0$ mL.

Step3: Calculate density

$D=\frac{50.0\ g}{50.0\ mL}=1.00$ g/mL

Step1: Calculate volume of object

The volume of a rectangular - shaped object $V=l\times w\times h$, where $l = 15.0$ cm, $w = 10.0$ cm and $h = 5.0$ cm. So $V=15.0\ cm\times10.0\ cm\times5.0\ cm = 750$ cm³.

Step2: Recall density formula

The formula for density is $D=\frac{m}{V}$, with $m = 450$ g.

Step3: Calculate density

$D=\frac{450\ g}{750\ cm^{3}}=0.6$ g/cm³

Answer:

The density of the wood is 600 kg/m³

2.