Engineering Mathematics

John Bird BSc

Chapter 4 Calculations and evaluation of formulae - all with Video Answers

Educators

Section 14

Exercises 14

03:38

Problem 1

state which type of error, or errors, have been made:
$25 \times 0.06 \times 1.4=0.21$
[order of magnitude error]

Jason Taylor-Pestell

Numerade Educator

02:05

state which type of error, or errors, have been made:
$137 \times 6.842=937.4$
$\left[\begin{array}{l}\text { Rounding-off error-should add 'correct } \\ \text { to } 4 \text { significant figures' or 'correct to } \\ 1 \text { decimal place' }\end{array}\right]$

Kim Trang Nguyen

Numerade Educator

03:38

Problem 3

state which type of error, or errors, have been made:
$\frac{24 \times 0.008}{12.6}=10.42$
[Blunder]

Jason Taylor-Pestell

Numerade Educator

01:44

Problem 4

state which type of error, or errors, have been made:
For a gas $p V=c$. When pressure $p=103400$ Pa and $V=0.54 \mathrm{~m}^3$ then $c=55836 \mathrm{~Pa} \mathrm{~m}^3$.

$$
\left[\begin{array}{l}
\text { Measured values, hence } \\
c=55800 \mathrm{~Pa} \mathrm{~m}^3
\end{array}\right]
$$

Robert Leedy

Numerade Educator

01:44

Problem 5

state which type of error, or errors, have been made:
$\frac{4.6 \times 0.07}{52.3 \times 0.274}=0.225$

$$
\left[\begin{array}{l}
\text { Order of magnitude error and rounding- } \\
\text { off error-should be } 0.0225 \text {, correct to } 3 \\
\text { significant figures or } 0.0225 \text {, } \\
\text { correct to } 4 \text { decimal places }
\end{array}\right]
$$

Ankit Gupta

Numerade Educator

02:30