Which of the following could be a unit of power?t99oe lwa :z/9nts8m) y l.krd

  By approximately how many powers of ten is the height/snd/g wthf 9/ of a human larger than the height of a grain of d9// /fthwgs nsand?

  What is the value ofz-cn()y( w nqbqgg-k 3 $\frac{6.3 \mu \mathrm{m} \times 10 \mathrm{GN}}{2.1 \mathrm{~ms}} ?$

  Which of the following is a fundamen/rl tbdz1:m8*pl.fmf 4b y1u ttal unit in the SI system?

  The volume of the Earth is approximately;)1we3rth uti $10^{12} \mathrm{~km}^3$ 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, the number of heartbeats of an averpjo( tbv f2h3 dzt-wnh 3,1y.wage adult d v.yz3bw3-ofphhwj n,t21t( human in a day.

  Which of the following contain si(36l ih3i5,dkxqh e/n.: zprhl l(su3 ca8ds one fundamental unit and one derived unit?

  If A=10.0 and B=0.50, which calculation will give the answer wit 5nll0ub8245wud j dsdh the most decimal placesddl 5djw20 ubsnu l458?

  A car has a mass of 1000kg. A mouse has a mass of 10g. What)k.p4d -gim na is the order of magnitude of the ratio betwem.p i )n4-gakden the mass of the car to that of the mouse?

  A train travels $39.1 \pm 0.4$ meters in $3.288 \pm 0.04$ 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 shas)l ;-/ot +i zdpj*qoepe of a cube with sides of $1.97 \mathrm{~m}$. Each side is measured with an uncertainty of $2.4 \%$. 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 squarsop19uo7t 2ery.r, amp la6g9e 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 $8.5 \%$ and $h$ is measured to $3 \%$, 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 metre4azy (6i7sx,kxp,;aiyx t 5 pz rule that is graduated in millimetres, ax6zi,sy a, 4zx;p ay7 itk(p5xs 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 $6.2 \% $ uncertainty in $V$ and a $0.9 \%$ uncertainty in $r$. What is the percentage uncertainty in $h$ ?  (数值) % (Remember to exclude the $\%$ symbol with your answer)

  The radius of a ball; bisp vjv*x7v 4.dw;coon is measured to be $19.0 \pm 0.9 \; cm$. 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 $1.6 \%$ and the uncertainty in $l$ is $5.7 \%$, 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 estimateipq zu z-:.k +pyhk4b,c:yn 8, ) q5rhbixyy9sd as $10.0 \mathrm{~m}, 4.0 \mathrm{~m}$ 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 differew23i fuys6*u ence ($V$) across a resistor is measured with a digital voltmeter to be $0.38 \; V$ . 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 sa ubta (;,p (l:way;4s 0 zupwqhsmf4+hme quantity which of the following can be ret4sh(:wa wu ;uhp,+map40 fbz( s;ylq duced?

  A student measures a distance four times. The readings are 37.8 cywkaa)m489d e a8dg3wm, 37.9 cm, 38.1 cm, 38.2 cm. What is the best estimate of8ad8gw3y a9d)4 aemkw this measurement?

  A student measures two lengths as followssk5g616dfwuv :a gg1barrzrei3s8 4*8 vf z1 a: $$a = (10 \pm 0.1) \; cm$$ $$b = (20 \pm 0.1) \; cm$$
Which of the following quantities has the largest percentage uncertainty?

  The time for two events, a and b, ar188lp4weq o0ye0 vjbve 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. Theorjasq7k .(x( sgy states that P should vary lineask sgx(j7q .(arly with Q.

  The length of a pencilf3giiv t5 p;4pybd ols1h)((o is measured using part of a measuring tape as shown below.b vi(dl1p) 3t4pi(sog y;foh5

What is the length of the pencil?

  The masses and weights of different objects are independently measurf a9fsz0d c: j4ng15used. The graph i f:95azfuc04s1nj gsd s a plot of weight versus mass that 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 ou rl,-5ho+ *n+tw ryo9 r,ewief a rectangular plate are measured, and the diagram shows the measured values with their uncr- ,errytouw*oe l+i5nh, 9+ wertainties.

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 wi9rp ,x39ah+zhb6v2 i5 ly s/ tbvd8abpth percentage uncertainty of 5%. The radius of the sphere is 6.0 ± ahibvx+l2 8b,9pv9ydh b3a s/ 6 zpt5r0.5 cm. What is the percentage uncertainty in the mass of the sphere?  (数值) % (Please do not include the % simbol in the blank)

  Experimental data has shus uc t7slw4u+vf7p .(own 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 accelerationuf/e,d4mc9tw r1 8ywa due to gravity produces the follomt1y8wu4a,we/fc 9 dr wing 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 usuq++h -bunn2 vrr ,:bbing a ruler, such that each measurement has an uncertainty ofqbn-,bu 2 n++:urvrbh $0.5 \mathrm{~cm} .$

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 6x q)wma2al;xbtm)+ys $(2.0 \pm 0.1) \mathrm{kg}$, what percentage uncertainty in the velocity will give a $6.5 \%$ 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 error. Which of the foll8,csgx)lqjn2r/q2n +9 oqgjf owing statements is ) 2nqx+98nf,sqrgjc2 /gjqol correct?

  A student measures a lek95b1q6zhgbw0c3tlhk. v : oj ngth five times. 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 ± 0.3 cm long)- /p7in qt4mwkza .yc is cut from a longer piece that is 12.6 ± 0.1 cm long. How lka-wny/7qt i)z .4 cpmong 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 $\pm 8 \%$. 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 ± 1.2 N is applied to a mass of 2.0 ± 0.10 kg, causing it to asw65 ;mi7mmp .h k2yrxccelerate. What is the percentage uncertainty of p h .si675m;mmwr2ky xits 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 ±3+ubi8 pj lz z7 *c;guev/e.pv 2.0 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) %