Which of the followingi rgx,xy-j, c4 could be a unit of power?

  By approximately how many powers of tcz-ywa pj0* k ,(hgb(ken is the height of a human larger than the height k(gw,h cj yp*k0(bza- of a grain of sand?

  What is the value of6lm, : zh.fqii /,tt+ndurw2l $\frac{6.3 \mu \mathrm{m} \times 10 \mathrm{GN}}{2.1 \mathrm{~ms}} ?$

  Which of the following is a fundamental unit in*,g a2 bvh/9ro0 udnwfm ,.ffa the SI system?

  The volume of the Earth is a0o b48d0,lym lfj+,te,g q sumqjl x(;pproximately $10^{12} \mathrm{~km}^3$ and the volume of a grain of sand is approximately $1 \mathrm{~mm}^3$. To the nearest order of magnitude, if the Earth was hollow, how many grains of sand could it contain?

  A farmer in Tanzania has an average life expectancy of 62 years. Which of the following is an estimate of his lifetime in seconds?

  Estimate, to the nearest order of magnitude, m2q8l 6 l8+knpoi+hsll da)(nthe number of heartbeats of an average adult human in a +(+6 i mq nh s82k8ll)allnodpday.

  Which of the following contain1 *io -ugx)-ukqyq+zms one fundamental unit and one derived unit?

  If A=10.0 and B=0.50, which calculation will give the answer with the mos7uqs) u(e zu doo/(;kut decima)u7qusude(zok u/ (o ;l places?

  A car has a mass of 1000kg. A mouse has a mass of 10g.g x;ku/kb1m l1go64lw hgrm77 What is the order of magnitude of the ratio between the mass of the car to that o17lm h 6xm;7ggu kko/lgr4 1wbf the mouse?

  A train travels $51.9 \pm 0.7$ meters in $11.090 \pm 0.05$ seconds. What is the absolute uncertainty in its speed?  (数值)  (Leave your answer to two significant figures, without units and without the $\pm$ symbol.)

  A water tank is the shape of a cube with sidesz6zkx8 o,uc in7:n6du+qpu /f of $3.95 \mathrm{~m}$. Each side is measured with an uncertainty of $0.7 \%$. What is the absolute uncertainty in the volume of the tank?  (数值)  (Give your answer without a unit and to 2 significant figures)

  A pyramid has a squar9c7s;c3mmgt3jjr xxi4is(n/ e base of side $x$ and height $h$. The volume $V$ of the pyramid is given by the expression:
$$V=\frac{x^2 h}{3}$$
If $V$ is measured to $5.6 \%$ and $h$ is measured to $4 \%$, what is the percentage uncertainty of $x ?$  (数值) % (Remember to exclude the $\%$ symbol with your answer)

  The length of a pencil is measured using part of a metre rule that is graduatei:j2b4e g/crjjt /9g md igi jjtj/g:c e/4rm 29bn millimetres, as shown below.

What is the length of the pencil?

  The volume $V$ of a cone of height $h$ and radius $r$ is given by the expression:
$$V=\frac{\pi r^2 h}{3}$$
In a particular experiment, there is a $5.7 \% $ uncertainty in $V$ and a $2.4 \%$ uncertainty in $r$. What is the percentage uncertainty in $h$ ?  (数值) % (Remember to exclude the $\%$ symbol with your answer)

  The radius of a balloon is measu8jsdmggsso x2,fx n27b 28 xywl 7*d;ured to be $22.8 \pm 1.9 \; cm$. What is the percentage uncertainty in the calculated volume of the balloon?  (数值) % (Remember to keep three significant figures and exclude the $\%$ symbol with your answer and treat the balloon as a sphere)

  The period $T$ of oscillation of a pendulum of length $l$ is given by:
$$T=2 \pi \sqrt{\frac{l}{g}} .$$
If the uncertainty in $g$ is $1.7 \%$ and the uncertainty in $l$ is $5.2 \%$, what is the percentage uncertainty in $T$ ?  (数值) % (only fill in numerical value without the % sign and keep two significant figures)

  The lengths of the sides of a room are estimated a cbmz:e.y m51f:i- vars $10.0 \mathrm{~m}, 4.0 \mathrm{~m}$ and $3.0 \mathrm{~m}$, each with an uncertainty of $\pm 8 \%$. What is the absolute uncertainty in the volume of the room?  (数值)  $m^3$ (Give your answer in $\mathrm{m}^3$ to two significant figures, without a unit.)

  The potential differlbnfs+cmydfy 8 w7 7(9ence ($V$) across a resistor is measured with a digital voltmeter to be $0.15 \; V$ . What is the percentage uncertainty in $V^2$ ?  (数值) % (only put numerical values in the blank and keep two significant figures.)

  By averaging three measurements of the same quantity which of the following cayx1o:(d bh ex4n be r:oe 4dx1xhy( beduced?

  A student measures a distance four times. The readings are 37.8 cm, 37.9 cm,9wo w 4am)xt9 /y-(nap:exvd 1xtytf9 38.1 cm, 38.2 cm. What is the best estimate of th t :tympftx1n d e/w9o)a4a xvx(-9wy9is measurement?

  A student measures two lengths as follows6q.uwzx1c1.0tst li y : $$a = (10 \pm 0.1) \; cm$$ $$b = (20 \pm 0.1) \; cm$$
Which of the following quantities has the largest percentage uncertainty?

  The time for two event0 b8h ks)yohb2s, a and b, are measured to be $(5.1 \pm 0.1)s$ and $(4.9 \pm 0.1)s$ respectively. In which of the following quantities is the fractional(percent) uncertainty the smallest?

  The variation of quantity P as quantity Q varies is plotted. Theory stg9gi,u .n fn;cates that P should vary linearly with.;9gg,n uincf Q.

  The length of a pencil is measured using pa3hiwdab: jg:oa*n pb. o4m )4urt of a measuring tape as shown below.3o4:h*b.jbn:ia ) ad 4omuwpg

What is the length of the pencil?

  The masses and weights of different w(kxi4j* k nwrwi8jkm8g k;*(objects are independently measured. The graph is a plot of weight versus mass that includes error 8k w* jwmgkirk;(xj(kw i*8n4 bars.

What do these experimental results suggest?

  The resistance $R$, and cross-sectional area $A$, of equal lengths of wire are measured at constant temperature and a graph of $R$ against $\frac{1}{A}$ is plotted. Which one of the following graphs would be obtained if $R$ is directly proportional to $\frac{1}{A}$ and if there is a significant systematic error in the measurement of $R ?$

  The lengths of the sides of a rectangular plate are mease:z6.p.93ps ifdedp klq qtdm) 49.nsured, and the diagram shows the measured values with their unlid.m ez9pq)qtpdp dnfe 9:.s k364s.certainties.

What is the percentage error in the area of the plate?   %. (Remember to exclude the % symbol with your answer.)

  The density of a solid sphere is measured with percentage uncertainty of e.c) d3zpmc0t 4%. The radius of the sphere is 4.8 ± 0.4 cm. What is the percentage uncertainty 3p ze0d). tmccin the mass of the sphere?  (数值) % (Please do not include the % simbol in the blank)

  Experimental data has shown thavpxh 41 rjan5:vj*g 8ft:
$$
P=\frac{g h^2}{u^3}
$$
where $g$ is a constant. If the percentage uncertainties in $h$ and $u$ are $a$ and $b$ respectively, what is the percentage uncertainty in $P ?$

  An experiment used to measure the acceleration due io dzem:-,m,5kns.zx une ,0ato gravity produces the follosxe5 mn, mzi,o-:ad.0nu ze,kwing results:
$\begin{array}{llllllllll}7.83 & 6.98 & 7.52 & 8.01 & 7.76 & 7.15 & 6.87 & 7.25 & 8.35 & 7.54\end{array}$
Which of the following statements is true about these data?
Are there random or systematic errors, both, or neither?
(Acceleration due to gravity, $g$, on Earth is usually taken as $9.81 \mathrm{~m} \mathrm{~s}^{-2}$ ).

  A rectangle was drawn usingig ou7qq-t, i 1p,ln0k a ruler, such that each measurement has an uncertainti ,n,- loq07pt1qgkiu y of $0.5 \mathrm{~cm} .$

What is the absolute uncertainty in the area of the entire rectangle (i.e. combined small and big rectangles), in $\mathrm{cm}^2$ ?    $cm^2$ (Do not write units with the answer. Give your answer to 2 significant figures.)

  For an object of mass l f-) ml zewesg(hl55jdn08; w$(2.0 \pm 0.1) \mathrm{kg}$, what percentage uncertainty in the velocity will give a $8.1 \%$ uncertainty in the kinetic energy ($KE = \frac{1}{2}mv^2$) ?  (数值) % (do not include the percent sign in your final result)

  An ammeter has a non-nnl-9(0gj::5fhu l*nz i) tmn3etq hihegligible zero offset error. Which of the following statemen5h:* qh9(nel-0mniuifj:gh) tzt ln3ts is correct?

  A student measures a length five trb125qs*ktu -hx.z)fvr dw( pwnk:7nz0q e3times. All of the measurements lie between $18.8 \mathrm{~cm}$ and $19.2 \mathrm{~cm}$. What should the student quote as the absolute uncertainty in the length? The absolute uncertainty is    $cm$ (Do not include the $\pm$ symbol nor the unit)

  A piece of string 9.5 ± 0.2 cm long ik7kb 0shcm(nl1mb2 /e 1dem1ys cut from a longer piece that is 12.6 ± 0.1 cm long. How long is l dek1cbhm1m7e1 kb2m/y s n0(the remaining piece of string?

  A current of value $I$ flows through a resistor of resistance $R$ and the power dissipated is $I^2 R$. The value of $I$ has an uncertainty of $\pm 2 \%$ and the value of $R$ has an uncertainty of $\pm 9 \%$. What is the percentage uncertainty in the calculated power dissipation?  (数值) % (Give your answer correct to two significant figures without the % sign.)

  A force of 10.0 ± 0.6 N is applied to a masg.o kea nq)e rv,d8aac9.(8d ms of 2.0 ± 0.08 kg, causing it to accelerate. Wh deva)(o,q.dc9kar8 .ae nmg8at is the percentage uncertainty of its acceleration?  (数值) % (do not include the percent sign in your result)

  The radius of a circle of wire is measured to bee6q ;jgpu:2 zp+dx1i.o 0 gdss 10.0 ± 1.2 cm.
What is the percentage error in the area of the loop?  (数值) %
What is the percentage error in the circumference of the loop?  (数值) %