Latihan – penukaran unit laju, ketumpatan dan tekanan

Anda boleh muat turun latihan-latihan ini di sini. (You can download the printable version of this exercise here.)

1. Lengkapkan penukaran unit bagi laju berikut.
1. Complete the following unit conversion of speed.

1. 90 kmh^-1 = __________ ms^-1
2. 110 kmh^-1 = __________ ms^-1
3. 1.3 ms^-1 = __________ kmh^-1
4. 8.12 ms^-1 = __________ kmh^-1

Jawapan:
a. $$\begin{array}{l}90km{j}^{{}_{-1}}\\ =\frac{90km}{1j}=\frac{90\times {10}^{3}m}{60\times 60s}=25m{s}^{-1}\end{array}$$ b. $$\begin{array}{l}110km{j}^{{}_{-1}}\\ =\frac{110km}{1j}=\frac{110\times {10}^{3}m}{60\times 60s}=30.6m{s}^{-1}\end{array}$$ c. $$\begin{array}{l}1.3m{s}^{{}_{-1}}\\ =\frac{1.3m}{1s}=\frac{\raisebox{1ex}{$1.3km$}\!\left/ \!\raisebox{-1ex}{$1000$}\right.}{\raisebox{1ex}{$1j$}\!\left/ \!\raisebox{-1ex}{$60\times 60$}\right.}=\frac{1.3km}{1000}\times \frac{60\times 60}{1j}=4.68km{j}^{{}_{-1}}\end{array}$$ d. $$\begin{array}{l}8.12m{s}^{{}_{-1}}\\ =\frac{8.12m}{1s}=\frac{\raisebox{1ex}{$8.12km$}\!\left/ \!\raisebox{-1ex}{$1000$}\right.}{\raisebox{1ex}{$1j$}\!\left/ \!\raisebox{-1ex}{$60\times 60$}\right.}=\frac{8.12km}{1000}\times \frac{60\times 60}{1j}=29.2km{h}^{{}_{-1}}\end{array}$$

2. Lengkapkan penukaran unit bagi ketumpatan dan tekanan berikut.
2. Complete the following unit conversion of density and pressure.

1. 760 kgm^-3 = __________ gcm^-3
2. 12000 kgm^-3 = __________ gcm^-3
3. 5.1 gcm^-3 = __________ kgm^-3
4. 3600 Nm^-2 = __________ Ncm^-2
5. 12x10⁶  Nm^-2 = __________ Ncm^-2
6. 1.5x10³ Nm^-2= __________ Ncm^-2
7. 3.16x10^-5 Ncm^-2= __________ Nm^-2
8. 7.1x10^-3 Ncm^-2 = __________ Nm^-2

Jawapan:
a. $$\begin{array}{l}760kg{m}^{-3}\\ =\frac{760kg}{1m^3}=\frac{760\times {10}^{3}g}{1000000c{m}^3}=0.76gc{m}^{-3}\end{array}$$ b. $$\begin{array}{l}12000kg{m}^{-3}\\ =\frac{12000kg}{1m^3}=\frac{12000\times {10}^{3}g}{1000000c{m}^3}=12gc{m}^{-3}\end{array}$$ c. $$\begin{array}{l}5.1gc{m}^{-3}\\ =\frac{5.1g}{1c{m}^3}=\frac{\raisebox{1ex}{$5.1$}\!\left/ \!\raisebox{-1ex}{$1000$}\right.kg}{\raisebox{1ex}{$1m^3$}\!\left/ \!\raisebox{-1ex}{$1000000$}\right.}=5100kg{m}^{-3}\end{array}$$ d. $$\begin{array}{l}3600N{m}^{-2}\\ =\frac{3600N}{1m^2}=\frac{3600N}{10000c{m}^2}=0.36Nc{m}^{-2}\end{array}$$ e. $$\begin{array}{l}12\times {10}^{6}N{m}^{-2}\\ =\frac{12\times {10}^{6}N}{1m^2}=\frac{12\times {10}^{6}N}{10000c{m}^2}=12\times {10}^{2}Nc{m}^{-2}\end{array}$$ f. $$\begin{array}{l}1.5\times {10}^{3}N{m}^{-2}\\ =\frac{1.5\times {10}^{3}N}{1m^2}=\frac{1.5\times {10}^{3}N}{10000c{m}^2}=0.15Nc{m}^{-2}\end{array}$$ g. $$\begin{array}{l}3.16\times {10}^{-5}Nc{m}^{-2}\\ =\frac{3.16\times {10}^{-5}N}{1c{m}^2}=\frac{3.16\times {10}^{-5}N}{\raisebox{1ex}{$1m^2$}\!\left/ \!\raisebox{-1ex}{$10000$}\right.}=0.316N{m}^{-2}\end{array}$$ h. $$\begin{array}{l}7.1\times {10}^{-3}Nc{m}^{-2}\\ =\frac{7.1\times {10}^{-3}N}{1c{m}^2}=\frac{7.1\times {10}^{-3}N}{\raisebox{1ex}{$1m^2$}\!\left/ \!\raisebox{-1ex}{$10000$}\right.}=71N{m}^{-2}\end{array}$$