Chapter 1, Problem 22P

(a)

Interpretation Introduction

Interpretation: The figure which is closest to the correct answer needs to be determined.

Concept Introduction: Unit conversion is a process that involves division or multiplication using a numerical factor which results in the conversion of one unit to other. It also involves the selection of correct number of significant digits and rounding.

Explanation of Solution

For the length of the baseball bat following values are given:

100 mm, 100 cm and 100 m.

A normal baseball bat is of 42 inches. Converting this into cm as follows:

$\left(\frac{2.54\text{cm}}{1\text{inch}}\right)\left(42\text{inch}\right)=106.68\text{cm}$

Converting 100 mm and 100 m to cm as follows:

Thus, 100 mm in cm will be:

$100\text{mm}\left(\frac{1\text{cm}}{10\text{mm}}\right)=10\text{cm}$

Now converting 100 m to cm:

$\frac{100\text{cm}}{1\text{m}}\left(100\text{m}\right)=10000\text{cm}$

Here, 10 cm and 10000 cm are not correct values for length of a baseball bat thus, the value which is closest to the correct value for a length of baseball bat is 100 cm.

(b)

Interpretation Introduction

Interpretation: The figure which is closest to the correct answer needs to be determined.

Concept Introduction: Unit conversion is a process that involves division or multiplication using a numerical factor which results in the conversion of one unit to other. It also involves the selection of correct number of significant digits and rounding.

Explanation of Solution

For the volume of a glass following values are given:

23 cc, 230 mL and 23 L.

A normal glass can hold a volume of 240 mL.

The volume 23centimeter cubes is equal to 23 mL and 23 L is equal to 23000 mL which is not possible.

Thus, the closest value to the correct answer is 230 mL.

(c)

Interpretation Introduction

Interpretation: The figure which is closest to the correct answer needs to be determined.

Concept Introduction: Unit conversion is a process that involves division or multiplication using a numerical factor which results in the conversion of one unit to other. It also involves the selection of correct number of significant digits and rounding.

Explanation of Solution

There are three figures given for the weight of a man:

75 mg, 75 g and 75 kg.

The average weight of a human body is 62 kg. This value is closer to 75 kg. The other figures are 75 mg and 75 g, the values in kg will be:

$75\text{mg}\left(\frac{{10}^{-6}\text{kg}}{1\text{mg}}\right)=7.5\times {10}^{-5}\text{kg}$

And,

$75\text{g}\left(\frac{{10}^{-3}\text{kg}}{1\text{g}}\right)=0.75\text{kg}$

Both the values are not possible for a weight of man thus, correct answer is 75 kg.

(d)

Interpretation Introduction

Interpretation: The figure which is closest to the correct answer needs to be determined.

Concept Introduction: Unit conversion is a process that involves division or multiplication using a numerical factor which results in the conversion of one unit to other. It also involves the selection of correct number of significant digits and rounding.

Explanation of Solution

The possible values for volume of tablespoon are given 15 mL, 150 mL and 1.5 L.

Here, 1.5 L can also be converted into mL as follows:

$\left(1.5\text{L}\right)\left(\frac{1000\text{mL}}{1\text{L}}\right)=1500\text{mL}$

The normal capacity of a tablespoon is 15 mL thus, 150 mL and 1.5 L or 1500 mL are incorrect values.

The correct value is 15 mL.

(e)

Interpretation Introduction

Interpretation: The figure which is closest to the correct answer needs to be determined.

Concept Introduction: Unit conversion is a process that involves division or multiplication using a numerical factor which results in the conversion of one unit to other. It also involves the selection of correct number of significant digits and rounding.

Explanation of Solution

The figures for weight of paper clip are given 50 mg, 50 g and 50 kg.

The mass of a regular paper clip is around 1 g.

Converting 50 mg and 50 kg to grams.

$\left(50\text{mg}\right)\left(\frac{{10}^{-3}\text{g}}{1\text{mg}}\right)=0.05\text{g}$

And,

$50\text{kg}\left(\frac{1000\text{g}}{1\text{kg}}\right)=50000\text{g}$

The value closer to 1 g is 0.05 g thus, 50 mg is correct answer.

(f)

Interpretation Introduction

Interpretation: The figure which is closest to the correct answer needs to be determined.

Concept Introduction: Unit conversion is a process that involves division or multiplication using a numerical factor which results in the conversion of one unit to other. It also involves the selection of correct number of significant digits and rounding.

Explanation of Solution

The figures for width of hand are given 100 mm 100 cm or 100 m.

The approximate width of hand is 3.5 inches.

Converting inches to mm as follows:

$3.5\text{inches}\left(\frac{25.4\text{mm}}{1\text{inch}}\right)=88.9\text{mm}$

The value is closer to 100 mm. Thus, 100 mm is correct answer.

(g)

Interpretation Introduction

Interpretation: The figure which is closest to the correct answer needs to be determined.

Concept Introduction: Unit conversion is a process that involves division or multiplication using a numerical factor which results in the conversion of one unit to other. It also involves the selection of correct number of significant digits and rounding.

Explanation of Solution

The given figures for the weight of a flash drive are 8 mg, 8 g and 8 kg.

Mostly all flash drive weigh less than 30 g.

Here, 8 mg is 0.008 g and 8 kg is 8000 g.

Thus, the closest value to the correct answer is 8 g.