Which of the following could be a unit of p:utjlxn )-.dc ower?

  By approximately how many powers of ten is the henh;q2 *cb xnp0ight of a human larger than thex*;hb0 nqpcn2 height of a grain of sand?

  What is the value of 0sba /-7wkzze $\frac{6.3 \mu \mathrm{m} \times 10 \mathrm{GN}}{2.1 \mathrm{~ms}} ?$

  Which of the following is a fundamads(gxc/*: c vkxq*hrt1/+rk3 p+b bs ental unit in the SI system?

  The volume of the Earth iles hjkjzsrl.5(pbin 0mt7*42 3:ig ds approximately $10^{12} \mathrm{~km}^3$ 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, h;w4065cehsayxd n f/ the number of heartbeats of an aver/ 64s ydw0hnafc;hx5eage adult human in a day.

  Which of the following contains one fundamental unit and oka7;hm,tzxn (g a 3op2ne derived unit?

  If A=10.0 and B=0.50, which cal .x fy27s6 /qco-eihhzculation will give the answer with the most decimal pohshxy -eiz.6q2fc7 /laces?

  A car has a mass of 1000kg. A mouse has a mass of 10g. What is td1mzow+afn)s- e): tr he order of magnitude of the ratio between the mass of the car to that of the moustaz)-nfw edr )+1 os:me?

  A train travels $73.2 \pm 0.3$ meters in $14.501 \pm 0.05$ 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 84 - * 5)mmvu 0x5mokzoottg8ldm)inn cube with sides of $2.89 \mathrm{~m}$. Each side is measured with an uncertainty of $0.2 \%$. 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 square base of 1;b i uxg,rbl-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 $8.2 \%$ 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 rulq7pc*7ru dbcv 6 .y(cke that is graduated in millimetres, as shown belowcc pdu.q7r*y67b vck(.

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 $3.7 \% $ uncertainty in $V$ and a $2.9 \%$ 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 measured to 6epzbqgv p8p3ai) (ai z6)pujd8r7 ;bbe $26.9 \pm 1.9 \; cm$. 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 $1.5 \%$ and the uncertainty in $l$ is $6.6 \%$, 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 skd yphmw5m :) cg;i d36nl35mwides of a room are estimated as $10.0 \mathrm{~m}, 4.0 \mathrm{~m}$ and $3.0 \mathrm{~m}$, each with an uncertainty of $\pm 2 \%$. 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 differxz - s3j /*4:n:hxu,trtwfd moence ($V$) across a resistor is measured with a digital voltmeter to be $0.47 \; V$ . 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 whic;-d* ao-qk+v.z 2ubncr v3 lp7 inf)hdh of the following can be r-);ak+cvdbi n p7q2nfh3z rvd l*u-.o educed?

  A student measures a distance four times. The ra 0gfj1 )aw/iueadings are 37.8 cm, 37.9 cm, 38.1 cm, 38.2 cm. What is thewj)i aafgu01 / best estimate of this measurement?

  A student measures tt8a4gqomz py;2,.m 8 kpxi w3nwo lengths as follows: $$a = (10 \pm 0.1) \; cm$$ $$b = (20 \pm 0.1) \; cm$$
Which of the following quantities has the largest percentage uncertainty?

  The time for two events, a and b, are f. 6 ny(goicdhk w6)5yd;l5su 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 quan)ab)jqg5 x zblx ):rw.tity P as quantity Q varies is plotted. Theory states that P should va)ra5:xjwxlg . z)b)b qry linearly with Q.

  The length of a pencil is measured using pjjz, z e5 sfcj:abjgx:o1* f us7vz(73art of a measuring tape as shown below.g(vsc7 3,bas 1fzfjzu:5jo7j:je *xz

What is the length of the pencil?

  The masses and weights of different objectylz)a7*pi1tvi l e(*ku- x wzj q5fc+3s are independently measured. The graph is a plot of weight versus mass th ( j7tkl*pyic )xlwziz - 1q3u*v+f5eaat includes error 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 recogd7:-x qu)vz3eegeu 4r:uu +tangular plate are measured, and the diagram shows the measured values with their un7)qee+ gxdg::ouz 3 e4u-rvuucertainties.

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 unoqwzr5gb4t +,ij6 b0dcertainty of 6%. The radius of the sphere is 5.2 ± 0.3 cm. What is the percentage uncertainty in the ma6ijg4,5r tb 0dqzo w+bss of the sphere?  (数值) % (Please do not include the % simbol in the blank)

  Experimental data has shown t uxu pjvzdk1;//w2i. that:
$$
P=\frac{g h^2}{u^3}
$$
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 y7kz s g+w)twu08e e:vacceleration due to gravity produces the following re8wtzguy:0ke)w s+ 7vesults:
$\begin{array}{llllllllll}7.83 & 6.98 & 7.52 & 8.01 & 7.76 & 7.15 & 6.87 & 7.25 & 8.35 & 7.54\end{array}$
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 using a ruler, such that each measurement has an uncerwks y0f.g4tmeu;9iu6db c, d *tainty d;twcs. id4 b 9myk06uufge ,*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 mas 1c,3sw/ fmw n2wepz8bs $(2.0 \pm 0.1) \mathrm{kg}$, what percentage uncertainty in the velocity will give a $7.8 \%$ 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-negligible zero offset erhosi) 0mixkj:vq+ 2;7o fjb,lror. Which of the following statements oi 70bm:jsl)vij;+k2, f hoxq is correct?

  A student measures a length five times. All of the measurements lie sex5r 2j0ngmyfg65l, 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 ± 0.4 ckn7d6t/m go 1xx*hr+hm long is cut from a longer piece that is 12.6 ± 0.2 cm lok ndhgx+6xo h7*1m/trng. How long is 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 $\pm 3 \%$ and the value of $R$ has an uncertainty of $\pm 2 \%$. 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 ± 0.2 N is applil ph85adpr8txl :6etw4o( pk;vr* gh5ed to a mass of 2.0 ± 0.17 kg, causing it to accelerate. What i*axtrevok;dw:6pl r 5h854 gph8t(pls 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 be 10.0 ± 1.1p 7phc3 ,pndvd;bi o;7 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) %