Which of the following could be a unit of power?w;y*/ z,cc)e1vhfk sf

  By approximately how many powers of v,cj3z z-3b;rh++ vd3h n2ki*jyb gmnten is the height of a human larger than the h2rk+n,z3b+jv-in mg v;db *3jzch3 hyeight of a grain of sand?

  What is the value of ph6kauxcp314)wivio cu2v 1j a 73w+ x$\frac{6.3 \mu \mathrm{m} \times 10 \mathrm{GN}}{2.1 \mathrm{~ms}} ?$

  Which of the following is a f4fbipz2/d5 t( m-qglzundamental unit in the SI system?

  The volume of the Earth is approxim3.w6djy kict (hk;9 cbately $10^{12} \mathrm{~km}^3$ 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 numberp8zng( p48(qqvj*rsy of heartbeats of an average adult human in a danq8 psryq4j*g pzv8((y.

  Which of the following contains one fundamental unit and one dp0p;y b: j8+ /j vt7uyvtq(uzwerived unit?

  If A=10.0 and B=0.50, e e 8n6r,3zcrcwhich calculation will give the answer with the most decimal pla,c8 6zecrr3en ces?

  A car has a mass of 1000kg8xxg onr4e+t*zf2tjv fnw/yq+-j )y 2. A mouse has a mass of 10g. What is the order of magnitude of the ratio between the mass oj+2o ry-4)*ftz2 8nx fgnexy/w +jqvtf the car to that of the mouse?

  A train travels $44.0 \pm 0.3$ meters in $4.746 \pm 0.06$ 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 sides otc*m2ciy5;jhzkf1rly(g: lr /v a:-nf $5.07 \mathrm{~m}$. Each side is measured with an uncertainty of $2.1 \%$. 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 squares b/:zz6 j87c nn0svkoaj)d.c 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 $10.0 \%$ and $h$ is measured to $5 \%$, 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 gr ghwqvy10s*ic,w,2 egaduated i ,,ec*0 qwi1ywv2g hsgn 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 $4.4 \% $ uncertainty in $V$ and a $3.1 \%$ 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 me(kc7s141kou7c lp h(,fwaim kueq1o( 4 luw5wasured to be $11.4 \pm 1.0 \; cm$. 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 $5.1 \%$, 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 e6b 5u--g)rkbszrs k j*stimated as $10.0 \mathrm{~m}, 4.0 \mathrm{~m}$ and $3.0 \mathrm{~m}$, each with an uncertainty of $\pm 10 \%$. 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 differencekhc6s3b6 8 lkk ($V$) across a resistor is measured with a digital voltmeter to be $0.26 \; V$ . 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 can c6 h+ bwr 4grus4-g4po cr46s4gu 4p+gho-br wbe reduced?

  A student measures a distance four times. The readings are 37.8 cm, 37;9: 0b yawqfaiib4 mt(.9 cm, 38.1 cm, 38.2 cm. What9(t: qiba;ymi0fb w a4 is the best estimate of this measurement?

  A student measures two lengths as follof-w1fi.mmh.uq b21i lws: $$a = (10 \pm 0.1) \; cm$$ $$b = (20 \pm 0.1) \; cm$$
Which of the following quantities has the largest percentage uncertainty?

  The time for two events, a and b, are measus4 k- -i+qjvoxred 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 i 3cmx9fm-1 naas plotted. Theory states that P should vary line afa91cm3x mn-arly with Q.

  The length of a pencil is measured using part of a measuring tape as 5: nbp)ssblkdl:f0.l shown below. s kl5)nfbdp:s0:bl.l

What is the length of the pencil?

  The masses and weights of different objects are ke*i1 htu3ey9 1ww- ejindependently measured. The graph is a plot of weight versus ma1i- ut3*eww 1jhy9eke ss 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 of a rectangular plate are measured, and the d ay2s,hpt 2v;yiagram shows 2;,shya 2pvtythe measured values with their uncertainties.

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 ob x +r87- n6u:vnzkln z13 (engb1trief 1%. The radius of the sphere is 2.8 ± 0.2 cm. What is the percentage uncertainty in the mass of thkrveu-6 7(:tzxb znnr3ilne gn1+81 b e sphere?  (数值) % (Please do not include the % simbol in the blank)

  Experimental data has s7t7z pxk- q-g 7zjhkw3hown 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 measua+3l y ybrjb2 ldpi7s9j k4 pct,d;;j5re the acceleration due to gravity produces the following results:l +p;9 bi,jjy lk ;d5j724yptsbcadr 3
$\begin{array}{llllllllll}7.83 & 6.98 & 7.52 & 8.01 & 7.76 & 7.15 & 6.87 & 7.25 & 8.35 & 7.54\end{array}$
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 c*cim.t p nj(62cwl) 1 m9gjvsa ruler, such that each measurement has an uncertaing2(l1nijw.m)vc9 cjm6s *ct pty 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 massnc5t2i14h pef5u+1 hofswj .f $(2.0 \pm 0.1) \mathrm{kg}$, 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-negligible zero offset errazx: edxipq7 -**nvd 8or. Which of the following statemen**d:zxx7avn d e8-pi qts is correct?

  A student measures a length five tim/q 84mrks9rga es. 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 is cut fromz2 (pj 0ae0bm r( mbke:ty68ax4gk cf+ a longer piece that is 12.6 ± 0.6 cm 04apb y 8b(2j:fe0cgt+e k a (mrmkx6zlong. 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 $\pm 1 \%$ 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 ± 1.6 N is applied to a masqs2 88gkka/ngzp3 o)8 vgg; ars of 2.0 ± 0.08 kg, causing it to accelerate. vrgagk3a8 2;gok/ng s8)pz q8 What is the percentage uncertainty of its acceleration?  (数值) % (do not include the percent sign in your result)

  The radius of a circle of wihuzs6z j/:d h f)j v1 48j/ulcayg9;mpre is measured to be 10.0 ± 1.7 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) %