[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:02.03,0:00:07.57,Default,,0000,0000,0000,,A formula is a recipe or a rule\Nfor doing something and it works
Dialogue: 0,0:00:07.57,0:00:10.74,Default,,0000,0000,0000,,every time it gives the\Nrelationship between different
Dialogue: 0,0:00:10.74,0:00:15.01,Default,,0000,0000,0000,,quantities. Some formerly a\Nstandard formally written down
Dialogue: 0,0:00:15.01,0:00:19.77,Default,,0000,0000,0000,,by Mathematicians and scientists\Nto cover a wide range of the
Dialogue: 0,0:00:19.77,0:00:21.06,Default,,0000,0000,0000,,relationships between different
Dialogue: 0,0:00:21.06,0:00:26.40,Default,,0000,0000,0000,,quantities. Others can be made\Nup such as that for a washing
Dialogue: 0,0:00:26.40,0:00:28.37,Default,,0000,0000,0000,,powder or a magician's memory
Dialogue: 0,0:00:28.37,0:00:30.61,Default,,0000,0000,0000,,trick. More of that later.
Dialogue: 0,0:00:31.53,0:00:36.30,Default,,0000,0000,0000,,Formally, usually use variables\Nand letters instead of numbers,
Dialogue: 0,0:00:36.30,0:00:41.60,Default,,0000,0000,0000,,and that gives the relationship.\NLet's have a look at.
Dialogue: 0,0:00:43.55,0:00:49.62,Default,,0000,0000,0000,,The formula for the area\Nof a circle A equals π R
Dialogue: 0,0:00:49.62,0:00:54.18,Default,,0000,0000,0000,,squared, where a is the\Narea of the circle.
Dialogue: 0,0:00:57.64,0:01:00.33,Default,,0000,0000,0000,,And R is the radius of\Nthe circle.
Dialogue: 0,0:01:04.11,0:01:07.83,Default,,0000,0000,0000,,This formula works every time\Nand shows the relationship.
Dialogue: 0,0:01:07.83,0:01:12.37,Default,,0000,0000,0000,,So we square the radius. We\Nmultiplied by pie and it
Dialogue: 0,0:01:12.37,0:01:16.09,Default,,0000,0000,0000,,gives us the area and it will\Nalways work.
Dialogue: 0,0:01:18.16,0:01:23.84,Default,,0000,0000,0000,,Imagine we have a circular lawn\Nwhere the radius is 3 meters.
Dialogue: 0,0:01:24.92,0:01:29.51,Default,,0000,0000,0000,,And we want to know how much\Nturf in square meters that we
Dialogue: 0,0:01:29.51,0:01:32.69,Default,,0000,0000,0000,,need to order so R is equal to 3
Dialogue: 0,0:01:32.69,0:01:38.05,Default,,0000,0000,0000,,meters. So what we're going\Nto do instead of writing are
Dialogue: 0,0:01:38.05,0:01:42.92,Default,,0000,0000,0000,,in our formula. We're going\Nto write the number 3, so A
Dialogue: 0,0:01:42.92,0:01:47.39,Default,,0000,0000,0000,,is equal to Π * 3 squared.\NNow, it's really important
Dialogue: 0,0:01:47.39,0:01:50.64,Default,,0000,0000,0000,,that we put the\Nmultiplication sign back in
Dialogue: 0,0:01:50.64,0:01:54.70,Default,,0000,0000,0000,,as soon as we put numbers\Nback in our formula.
Dialogue: 0,0:01:57.00,0:02:03.90,Default,,0000,0000,0000,,Π * 3 squared is π\N* 9, giving us 28.3.
Dialogue: 0,0:02:04.53,0:02:06.30,Default,,0000,0000,0000,,So the area of our.
Dialogue: 0,0:02:07.31,0:02:12.88,Default,,0000,0000,0000,,Lawn is going to be 28.3\Nmeters squared, so we're
Dialogue: 0,0:02:12.88,0:02:18.45,Default,,0000,0000,0000,,going to need at least 29\Nmeters squared of turf.
Dialogue: 0,0:02:24.18,0:02:28.65,Default,,0000,0000,0000,,There are many formerly that\Nrelates to the area of 2D
Dialogue: 0,0:02:28.65,0:02:32.30,Default,,0000,0000,0000,,objects and also to the volume\Nof 3D solids.
Dialogue: 0,0:02:33.12,0:02:36.24,Default,,0000,0000,0000,,Let's have a look at one. Now\Nlet's say we want to find the
Dialogue: 0,0:02:36.24,0:02:37.13,Default,,0000,0000,0000,,volume of a football.
Dialogue: 0,0:02:39.87,0:02:45.98,Default,,0000,0000,0000,,Now football is a sphere, so we\Nwant the formula for the volume
Dialogue: 0,0:02:45.98,0:02:52.09,Default,,0000,0000,0000,,of a sphere and that's V equals\N4 thirds of Π R cubed.
Dialogue: 0,0:02:52.76,0:02:57.54,Default,,0000,0000,0000,,And let's say that the\Nradius of a sphere are
Dialogue: 0,0:02:57.54,0:02:59.45,Default,,0000,0000,0000,,football is 10 centimeters.
Dialogue: 0,0:03:00.93,0:03:07.24,Default,,0000,0000,0000,,So in our formula to workout the\Nvolume instead of writing, are
Dialogue: 0,0:03:07.24,0:03:12.50,Default,,0000,0000,0000,,we going to write 10\Ncentimeters, so V equals 4
Dialogue: 0,0:03:12.50,0:03:17.24,Default,,0000,0000,0000,,thirds π multiplied, again\Nremembering to put the multiply
Dialogue: 0,0:03:17.24,0:03:23.55,Default,,0000,0000,0000,,symbol in and instead of are we\Nwriting 10, so 10 cubed?
Dialogue: 0,0:03:25.24,0:03:27.30,Default,,0000,0000,0000,,And if we calculate all of that.
Dialogue: 0,0:03:27.88,0:03:35.12,Default,,0000,0000,0000,,We end up with the\Nvolume equaling 4189, so the
Dialogue: 0,0:03:35.12,0:03:42.36,Default,,0000,0000,0000,,volume of the football since\Nthe radius was in centimeters
Dialogue: 0,0:03:42.36,0:03:45.98,Default,,0000,0000,0000,,will be 4189 centimeters cubed.
Dialogue: 0,0:03:54.69,0:03:58.47,Default,,0000,0000,0000,,There are many formerly relating\Nto scientific principles.
Dialogue: 0,0:03:59.71,0:04:03.87,Default,,0000,0000,0000,,And we're going to have a look\Nat Newton's second law.
Dialogue: 0,0:04:09.16,0:04:15.16,Default,,0000,0000,0000,,And that law relates force\Nwith mass and acceleration.
Dialogue: 0,0:04:16.34,0:04:22.24,Default,,0000,0000,0000,,And the formula is F equals\NMA mass times acceleration.
Dialogue: 0,0:04:23.83,0:04:28.25,Default,,0000,0000,0000,,Let's imagine a circus artist is\Ngoing to be fired from the
Dialogue: 0,0:04:28.25,0:04:32.34,Default,,0000,0000,0000,,barrel. And he's going\Nto be fired horizontally
Dialogue: 0,0:04:32.34,0:04:36.38,Default,,0000,0000,0000,,and the mass of a circus\Nartist is 60 kilograms.
Dialogue: 0,0:04:37.81,0:04:42.57,Default,,0000,0000,0000,,And he's going to be fired\Nat an acceleration of 2.5
Dialogue: 0,0:04:42.57,0:04:44.30,Default,,0000,0000,0000,,meters per second squared.
Dialogue: 0,0:04:45.51,0:04:49.50,Default,,0000,0000,0000,,Our formula is F equals MA.
Dialogue: 0,0:04:50.78,0:04:53.79,Default,,0000,0000,0000,,So instead of em, we're\Ngoing to write 60.
Dialogue: 0,0:04:56.11,0:04:58.48,Default,,0000,0000,0000,,And instead of a, we're going to
Dialogue: 0,0:04:58.48,0:05:02.23,Default,,0000,0000,0000,,put 2.5. But again, because\Nwe're putting numbers in.
Dialogue: 0,0:05:02.86,0:05:07.92,Default,,0000,0000,0000,,Instead of the letters, we must\Nremember to put the multiply
Dialogue: 0,0:05:07.92,0:05:12.52,Default,,0000,0000,0000,,sign back in so it'll be 60\Ntimes by 2.5.
Dialogue: 0,0:05:13.71,0:05:21.17,Default,,0000,0000,0000,,That gives us 150, so the\Nforce on our circus artists is
Dialogue: 0,0:05:21.17,0:05:25.48,Default,,0000,0000,0000,,150 newtons. And Newton is\Na unit of force.
Dialogue: 0,0:05:30.35,0:05:32.84,Default,,0000,0000,0000,,Let's look at an equation\Nof motion.
Dialogue: 0,0:05:34.21,0:05:37.16,Default,,0000,0000,0000,,Z equals you plus 80.
Dialogue: 0,0:05:38.92,0:05:41.93,Default,,0000,0000,0000,,Fee represents final speed.
Dialogue: 0,0:05:45.12,0:05:47.01,Default,,0000,0000,0000,,You initial speed.
Dialogue: 0,0:05:50.77,0:05:52.58,Default,,0000,0000,0000,,Hey, is acceleration.
Dialogue: 0,0:05:56.00,0:05:57.46,Default,,0000,0000,0000,,Auntie is time.
Dialogue: 0,0:05:59.52,0:06:03.27,Default,,0000,0000,0000,,And imagine that we've got some\Nvalues for you A&T.
Dialogue: 0,0:06:04.03,0:06:05.04,Default,,0000,0000,0000,,So you.
Dialogue: 0,0:06:06.64,0:06:07.70,Default,,0000,0000,0000,,Equal to 5.
Dialogue: 0,0:06:09.11,0:06:12.87,Default,,0000,0000,0000,,A is equal to two and T\Nis equal to 3.
Dialogue: 0,0:06:14.04,0:06:18.30,Default,,0000,0000,0000,,So to calculate V, the final\Nspeed, we're going to
Dialogue: 0,0:06:18.30,0:06:21.28,Default,,0000,0000,0000,,substitute these numbers\Ninstead of these letters.
Dialogue: 0,0:06:22.52,0:06:29.10,Default,,0000,0000,0000,,So instead of you, we write 5\Ninstead of a. It's two, we must
Dialogue: 0,0:06:29.10,0:06:33.33,Default,,0000,0000,0000,,write the multiply sign because\Nwe're now putting numbers
Dialogue: 0,0:06:33.33,0:06:34.74,Default,,0000,0000,0000,,instead of letters.
Dialogue: 0,0:06:35.33,0:06:37.79,Default,,0000,0000,0000,,And instead of T we write 3.
Dialogue: 0,0:06:38.75,0:06:42.53,Default,,0000,0000,0000,,Now we've got a good\Nopportunity here to look at
Dialogue: 0,0:06:42.53,0:06:46.69,Default,,0000,0000,0000,,our order of operations. If\Nwe were to start from the
Dialogue: 0,0:06:46.69,0:06:51.22,Default,,0000,0000,0000,,left and work through to the\Nright, we would be in error
Dialogue: 0,0:06:51.22,0:06:54.25,Default,,0000,0000,0000,,because we should do\Nmultiplying before we do
Dialogue: 0,0:06:54.25,0:06:57.65,Default,,0000,0000,0000,,addition. So a quick\Nreminder of our order of
Dialogue: 0,0:06:57.65,0:06:59.16,Default,,0000,0000,0000,,operations with Bob Mass.
Dialogue: 0,0:07:01.41,0:07:06.68,Default,,0000,0000,0000,,Where the B stands for brackets,\Nthe apfa powers.
Dialogue: 0,0:07:08.09,0:07:12.40,Default,,0000,0000,0000,,Steve for divide\Nand for multiply.
Dialogue: 0,0:07:13.87,0:07:15.16,Default,,0000,0000,0000,,A for addition.
Dialogue: 0,0:07:16.90,0:07:18.61,Default,,0000,0000,0000,,And S for subtraction.
Dialogue: 0,0:07:22.01,0:07:26.62,Default,,0000,0000,0000,,So multiply comes before\Naddition, so we need to do
Dialogue: 0,0:07:26.62,0:07:32.61,Default,,0000,0000,0000,,2 * 3 before we do the\Naddition, so it's 5 + 6,
Dialogue: 0,0:07:32.61,0:07:35.38,Default,,0000,0000,0000,,giving us an answer of 11.
Dialogue: 0,0:07:42.88,0:07:48.24,Default,,0000,0000,0000,,Let's look at another equation\Nof motion. This time V squared
Dialogue: 0,0:07:48.24,0:07:51.16,Default,,0000,0000,0000,,equals U squared plus 2A S.
Dialogue: 0,0:07:52.86,0:07:55.97,Default,,0000,0000,0000,,Again, the final speed.
Dialogue: 0,0:07:59.36,0:08:01.17,Default,,0000,0000,0000,,You initial speed.
Dialogue: 0,0:08:05.18,0:08:07.13,Default,,0000,0000,0000,,Hey Accelleration.
Dialogue: 0,0:08:10.61,0:08:13.11,Default,,0000,0000,0000,,And S distance traveled.
Dialogue: 0,0:08:15.36,0:08:18.10,Default,,0000,0000,0000,,And imagine we've got a Cliff.
Dialogue: 0,0:08:20.15,0:08:24.70,Default,,0000,0000,0000,,And we throw a stone off the top\Nof the Cliff and we'd like to
Dialogue: 0,0:08:24.70,0:08:27.72,Default,,0000,0000,0000,,know the speed with which it\Nhits the water below.
Dialogue: 0,0:08:28.81,0:08:31.52,Default,,0000,0000,0000,,And the Cliff is\N100 meters high.
Dialogue: 0,0:08:33.35,0:08:37.05,Default,,0000,0000,0000,,So we know that you\Nare initial speed.
Dialogue: 0,0:08:38.42,0:08:42.84,Default,,0000,0000,0000,,Is zero 'cause we're dropping\Nthe stone from rest at the top?
Dialogue: 0,0:08:45.08,0:08:49.20,Default,,0000,0000,0000,,Our acceleration is the\Nacceleration due to gravity, so
Dialogue: 0,0:08:49.20,0:08:51.49,Default,,0000,0000,0000,,that's 9.8 meters per second
Dialogue: 0,0:08:51.49,0:08:56.84,Default,,0000,0000,0000,,squared. And as the distance\Nthat it falls is 100 meters.
Dialogue: 0,0:08:58.55,0:09:02.06,Default,,0000,0000,0000,,So instead of the letters\Nin our formula, we
Dialogue: 0,0:09:02.06,0:09:03.23,Default,,0000,0000,0000,,substitute the numbers.
Dialogue: 0,0:09:04.47,0:09:06.11,Default,,0000,0000,0000,,UO
Dialogue: 0,0:09:07.45,0:09:14.60,Default,,0000,0000,0000,,plus two times\Na 9.8 times
Dialogue: 0,0:09:14.60,0:09:16.98,Default,,0000,0000,0000,,S 100.
Dialogue: 0,0:09:21.69,0:09:28.27,Default,,0000,0000,0000,,That works out at\N1960. Sophie squared is
Dialogue: 0,0:09:28.27,0:09:34.71,Default,,0000,0000,0000,,1960. So to calculate V,\Nthe final speed when it
Dialogue: 0,0:09:34.71,0:09:40.78,Default,,0000,0000,0000,,hits the water, we need to\Nsquare root 1960 and that
Dialogue: 0,0:09:40.78,0:09:44.09,Default,,0000,0000,0000,,gives us an answer of 44.
Dialogue: 0,0:09:46.04,0:09:46.94,Default,,0000,0000,0000,,And because.
Dialogue: 0,0:09:48.73,0:09:53.13,Default,,0000,0000,0000,,Our units are meters per second\Nsquared for acceleration in
Dialogue: 0,0:09:53.13,0:09:57.97,Default,,0000,0000,0000,,meters for the distance that\Nit's fallen, the velocity is 44
Dialogue: 0,0:09:57.97,0:09:59.29,Default,,0000,0000,0000,,meters per second.
Dialogue: 0,0:10:05.75,0:10:12.03,Default,,0000,0000,0000,,Another equation of motion is S\Nequals UT plus a half 80
Dialogue: 0,0:10:12.03,0:10:15.58,Default,,0000,0000,0000,,squared. What S is the distance?
Dialogue: 0,0:10:18.38,0:10:20.85,Default,,0000,0000,0000,,You is the initial speed.
Dialogue: 0,0:10:24.98,0:10:26.34,Default,,0000,0000,0000,,T is time.
Dialogue: 0,0:10:28.24,0:10:30.03,Default,,0000,0000,0000,,A accelerations.
Dialogue: 0,0:10:33.36,0:10:35.10,Default,,0000,0000,0000,,And the final to the same as
Dialogue: 0,0:10:35.10,0:10:40.28,Default,,0000,0000,0000,,this one time. Not so much in\Nthis time that we have a well.
Dialogue: 0,0:10:42.87,0:10:46.51,Default,,0000,0000,0000,,And we want to find out\Nhow deep the well is.
Dialogue: 0,0:10:48.52,0:10:50.97,Default,,0000,0000,0000,,And what we do is we drop a\Nstone down the well.
Dialogue: 0,0:10:57.28,0:11:01.78,Default,,0000,0000,0000,,Use the initial speed of the\Nstone is 0 because we dropped
Dialogue: 0,0:11:01.78,0:11:03.66,Default,,0000,0000,0000,,it. It started at rest.
Dialogue: 0,0:11:04.99,0:11:09.10,Default,,0000,0000,0000,,Let's say it takes 3 seconds for\Nthe stone to hit the bottom.
Dialogue: 0,0:11:10.66,0:11:16.68,Default,,0000,0000,0000,,And AR acceleration is that due\Nto gravity of 9.8 meters per
Dialogue: 0,0:11:16.68,0:11:22.12,Default,,0000,0000,0000,,second squared. So instead of\Nwriting you T&A in our formula,
Dialogue: 0,0:11:22.12,0:11:25.58,Default,,0000,0000,0000,,we're going to substitute and\Nput these values in.
Dialogue: 0,0:11:26.76,0:11:34.02,Default,,0000,0000,0000,,So S equals you\N0 multiplied by T3.
Dialogue: 0,0:11:34.99,0:11:40.57,Default,,0000,0000,0000,,Plus half multiplied\Nby 9.8.
Dialogue: 0,0:11:41.68,0:11:44.19,Default,,0000,0000,0000,,Multiplied by T squared.
Dialogue: 0,0:11:45.56,0:11:49.17,Default,,0000,0000,0000,,So we put all the figures in.\NNow we can carry out the
Dialogue: 0,0:11:49.17,0:11:56.84,Default,,0000,0000,0000,,calculation. 0 * 3 zero\Nplus half of 9.8 four point
Dialogue: 0,0:11:56.84,0:12:00.83,Default,,0000,0000,0000,,9 * 3 squared is 9.
Dialogue: 0,0:12:02.63,0:12:07.23,Default,,0000,0000,0000,,That gives an answer of 44 to\Nthe nearest whole number. And
Dialogue: 0,0:12:07.23,0:12:10.67,Default,,0000,0000,0000,,because our units are meters\Nper second squared and
Dialogue: 0,0:12:10.67,0:12:14.50,Default,,0000,0000,0000,,seconds, the depth of the\Nworld will be 44 meters.
Dialogue: 0,0:12:20.13,0:12:23.97,Default,,0000,0000,0000,,Let's have a look at the formula\Nfor kinetic energy.
Dialogue: 0,0:12:26.07,0:12:29.86,Default,,0000,0000,0000,,Kinetic energy equals 1/2 MV
Dialogue: 0,0:12:29.86,0:12:36.86,Default,,0000,0000,0000,,squared. Where M represents mass\Nand the is the speed that the
Dialogue: 0,0:12:36.86,0:12:38.85,Default,,0000,0000,0000,,mass is traveling at.
Dialogue: 0,0:12:39.53,0:12:44.100,Default,,0000,0000,0000,,The amount of work done, kinetic\Nenergy. Let's compare a sprinter
Dialogue: 0,0:12:44.100,0:12:50.46,Default,,0000,0000,0000,,running and the work that is\Ndone by the sprinter running
Dialogue: 0,0:12:50.46,0:12:56.43,Default,,0000,0000,0000,,with that of a truck. So the\Nsprinter is mass 70 kilos.
Dialogue: 0,0:12:57.83,0:13:02.18,Default,,0000,0000,0000,,And the running at a speed of 10\Nmeters per second.
Dialogue: 0,0:13:03.52,0:13:04.68,Default,,0000,0000,0000,,Another truck
Dialogue: 0,0:13:05.83,0:13:09.06,Default,,0000,0000,0000,,has a mass of 2000 kilos.
Dialogue: 0,0:13:10.47,0:13:16.69,Default,,0000,0000,0000,,And that's going forward at a\Nspeed of 20 meters per second.
Dialogue: 0,0:13:17.60,0:13:21.87,Default,,0000,0000,0000,,So let's compare how much\Nwork they're doing. So for
Dialogue: 0,0:13:21.87,0:13:22.72,Default,,0000,0000,0000,,this printer.
Dialogue: 0,0:13:25.08,0:13:31.67,Default,,0000,0000,0000,,The kinetic energy equals 1/2.\NThe mass is 70.
Dialogue: 0,0:13:33.63,0:13:36.62,Default,,0000,0000,0000,,The velocity is 10 squared.
Dialogue: 0,0:13:37.95,0:13:41.14,Default,,0000,0000,0000,,So we have 3500.
Dialogue: 0,0:13:42.84,0:13:43.97,Default,,0000,0000,0000,,For the truck.
Dialogue: 0,0:13:45.76,0:13:51.53,Default,,0000,0000,0000,,The kinetic energy again\Nis 1/2 instead of the M
Dialogue: 0,0:13:51.53,0:13:53.26,Default,,0000,0000,0000,,we write 2000.
Dialogue: 0,0:13:54.98,0:13:59.78,Default,,0000,0000,0000,,And instead of the V, we've got\N20 to be squared.
Dialogue: 0,0:14:01.01,0:14:04.65,Default,,0000,0000,0000,,And that works out at 400,000.
Dialogue: 0,0:14:06.26,0:14:10.74,Default,,0000,0000,0000,,So the kinetic energy of\Nthe truck is more than 100
Dialogue: 0,0:14:10.74,0:14:13.59,Default,,0000,0000,0000,,times greater than that of\Nthe sprinter.
Dialogue: 0,0:14:14.80,0:14:18.47,Default,,0000,0000,0000,,I haven't written the units\Ndown, but for kinetic energy
Dialogue: 0,0:14:18.47,0:14:19.20,Default,,0000,0000,0000,,there jewels.
Dialogue: 0,0:14:23.95,0:14:29.84,Default,,0000,0000,0000,,Let's look now at the formula\Nfor the period of a pendulum
Dialogue: 0,0:14:29.84,0:14:33.77,Default,,0000,0000,0000,,where T equals 2π root L over G.
Dialogue: 0,0:14:34.72,0:14:37.54,Default,,0000,0000,0000,,What city is the period of\Nthe pendulum?
Dialogue: 0,0:14:43.99,0:14:47.30,Default,,0000,0000,0000,,And that means how long the
Dialogue: 0,0:14:47.30,0:14:53.04,Default,,0000,0000,0000,,pendulum takes. To go from\None side of its motion to the
Dialogue: 0,0:14:53.04,0:14:56.68,Default,,0000,0000,0000,,other and then back again. So\Nthat's the period.
Dialogue: 0,0:14:58.18,0:15:01.34,Default,,0000,0000,0000,,L is the length of the pendulum.
Dialogue: 0,0:15:06.32,0:15:09.21,Default,,0000,0000,0000,,And she is the acceleration.
Dialogue: 0,0:15:11.82,0:15:13.07,Default,,0000,0000,0000,,Due to gravity.
Dialogue: 0,0:15:17.09,0:15:20.36,Default,,0000,0000,0000,,Which is 9.8 meters\Nper second squared.
Dialogue: 0,0:15:21.78,0:15:25.32,Default,,0000,0000,0000,,Let's imagine we've got a\Ngrand father Clock, and the
Dialogue: 0,0:15:25.32,0:15:28.86,Default,,0000,0000,0000,,length of the pendulum L is\Nequal to 1 meter.
Dialogue: 0,0:15:30.07,0:15:32.18,Default,,0000,0000,0000,,So in our formula.
Dialogue: 0,0:15:33.72,0:15:41.38,Default,,0000,0000,0000,,Going to put 2π multiplied by\Nthe square root L is 1
Dialogue: 0,0:15:41.38,0:15:45.20,Default,,0000,0000,0000,,meter divided by G is 9.8.
Dialogue: 0,0:15:48.05,0:15:55.27,Default,,0000,0000,0000,,And that gives us 2π. Now, if\Nwe calculate 1 / 9.8 and then
Dialogue: 0,0:15:55.27,0:15:57.34,Default,,0000,0000,0000,,square root the answer.
Dialogue: 0,0:15:58.81,0:16:05.39,Default,,0000,0000,0000,,We get 0.319 *\N2 and by pie
Dialogue: 0,0:16:05.39,0:16:11.14,Default,,0000,0000,0000,,and we end up\Nwith two .007.
Dialogue: 0,0:16:11.82,0:16:18.44,Default,,0000,0000,0000,,So the period of the pendulum to\Nthe nearest second is T equals 2
Dialogue: 0,0:16:18.44,0:16:23.17,Default,,0000,0000,0000,,seconds because we've used the\Nunits of meters per second
Dialogue: 0,0:16:23.17,0:16:24.59,Default,,0000,0000,0000,,squared and meters.
Dialogue: 0,0:16:29.16,0:16:33.26,Default,,0000,0000,0000,,That was a selection of standard\Nformerly now for the magicians
Dialogue: 0,0:16:33.26,0:16:37.36,Default,,0000,0000,0000,,memory trick. I've got a\Nselection of 30 or so cards
Dialogue: 0,0:16:37.36,0:16:40.80,Default,,0000,0000,0000,,here, each with eight digit\Nnumbers on, and if I could have
Dialogue: 0,0:16:40.80,0:16:42.80,Default,,0000,0000,0000,,a helper to select one at random
Dialogue: 0,0:16:42.80,0:16:47.42,Default,,0000,0000,0000,,for me. Now, if you could\Ngive me the two digit card
Dialogue: 0,0:16:47.42,0:16:50.94,Default,,0000,0000,0000,,number which is on the top\Nleft hand corner, I'll tell
Dialogue: 0,0:16:50.94,0:16:54.46,Default,,0000,0000,0000,,you the 8 digit number on\Nthe card number 14 #14.
Dialogue: 0,0:16:55.75,0:17:02.17,Default,,0000,0000,0000,,OK, the\N8 digit
Dialogue: 0,0:17:02.17,0:17:05.37,Default,,0000,0000,0000,,number is
Dialogue: 0,0:17:05.37,0:17:11.17,Default,,0000,0000,0000,,314-5943. 7, is that\Nright? That's correct, very
Dialogue: 0,0:17:11.17,0:17:17.41,Default,,0000,0000,0000,,good. OK would like to try\Nanother one, just to show that
Dialogue: 0,0:17:17.41,0:17:24.17,Default,,0000,0000,0000,,it's not a fluke. Can you give\Nme the two digit number again
Dialogue: 0,0:17:24.17,0:17:27.81,Default,,0000,0000,0000,,#13 #13? So the 8 digit number
Dialogue: 0,0:17:27.81,0:17:33.68,Default,,0000,0000,0000,,is 29101. 123, is that correct?\NThat's correct, good thank you
Dialogue: 0,0:17:33.68,0:17:37.87,Default,,0000,0000,0000,,very much. Well, I haven't\Nactually memorized all 30
Dialogue: 0,0:17:37.87,0:17:43.92,Default,,0000,0000,0000,,numbers that are here. I'm using\Na formula, so let's have a look
Dialogue: 0,0:17:43.92,0:17:48.56,Default,,0000,0000,0000,,now at the numbers and show you\Nwhat I did.
Dialogue: 0,0:17:51.06,0:17:54.96,Default,,0000,0000,0000,,Now the only information I was\Ngiven was the card number. This
Dialogue: 0,0:17:54.96,0:17:56.91,Default,,0000,0000,0000,,number at the top left hand
Dialogue: 0,0:17:56.91,0:18:02.74,Default,,0000,0000,0000,,corner. So I had to work out the\N8 digit number from that card
Dialogue: 0,0:18:02.74,0:18:09.67,Default,,0000,0000,0000,,number. Now the formula I\Nwas using was 2 N at
Dialogue: 0,0:18:09.67,0:18:13.44,Default,,0000,0000,0000,,three. What end represents\Nmy card number?
Dialogue: 0,0:18:17.13,0:18:21.73,Default,,0000,0000,0000,,So for example, the number 10 if\NN is equal to 10.
Dialogue: 0,0:18:22.83,0:18:30.09,Default,,0000,0000,0000,,Then I would do 2 times by 10 at\Nthree, which gives Me 2 * 10 is
Dialogue: 0,0:18:30.09,0:18:36.49,Default,,0000,0000,0000,,20 at 323, so that gives me my\Nfirst 2 digits of the number two
Dialogue: 0,0:18:36.49,0:18:42.90,Default,,0000,0000,0000,,and three, and then what I do is\Nadd the two digits to get the
Dialogue: 0,0:18:42.90,0:18:45.46,Default,,0000,0000,0000,,third number. SO2AD3 gives me 5.
Dialogue: 0,0:18:46.39,0:18:51.01,Default,,0000,0000,0000,,Then the next number comes from\Nadding the previous 2 digits.
Dialogue: 0,0:18:51.01,0:18:53.53,Default,,0000,0000,0000,,Three at 5 gives me 8.
Dialogue: 0,0:18:54.24,0:18:59.10,Default,,0000,0000,0000,,Five at 8 gives me 13, so I'm\Ngoing to take the 10 away and
Dialogue: 0,0:18:59.10,0:19:00.72,Default,,0000,0000,0000,,just write down the three.
Dialogue: 0,0:19:01.64,0:19:06.01,Default,,0000,0000,0000,,8 at three gives me 11. Again,\NI'm going to take the 10 away.
Dialogue: 0,0:19:06.62,0:19:12.28,Default,,0000,0000,0000,,And write down the one three add\None gives me four and one add 4
Dialogue: 0,0:19:12.28,0:19:17.55,Default,,0000,0000,0000,,gives me 5, so there's my 8\Ndigit number and all this I was
Dialogue: 0,0:19:17.55,0:19:19.44,Default,,0000,0000,0000,,given was the card number.
Dialogue: 0,0:19:20.65,0:19:26.36,Default,,0000,0000,0000,,OK, let's show you another one.\NLet's take this one an is 6.
Dialogue: 0,0:19:27.56,0:19:33.95,Default,,0000,0000,0000,,So 6 is going into my formula to\Nworkout the first 2 digits, so 2
Dialogue: 0,0:19:33.95,0:19:40.77,Default,,0000,0000,0000,,* 6 + 3 two 6 is a 12\Nadd. Three gives me 15, so the
Dialogue: 0,0:19:40.77,0:19:46.73,Default,,0000,0000,0000,,first 2 digits are one and five.\NThen I add one and five that
Dialogue: 0,0:19:46.73,0:19:53.12,Default,,0000,0000,0000,,gives me 6 for the 3rd digit I\Nadd five and six. That gives me
Dialogue: 0,0:19:53.12,0:19:58.23,Default,,0000,0000,0000,,11. I take away the 10 and one\Nis the next digit.
Dialogue: 0,0:19:58.88,0:20:00.11,Default,,0000,0000,0000,,Six at one.
Dialogue: 0,0:20:00.19,0:20:01.100,Default,,0000,0000,0000,,Gives Me 7 for the next one.
Dialogue: 0,0:20:02.74,0:20:05.41,Default,,0000,0000,0000,,One at 7 gives me 8.
Dialogue: 0,0:20:06.20,0:20:12.17,Default,,0000,0000,0000,,7 add 8 gives me 15. I take the\N10 away, so I write down just
Dialogue: 0,0:20:12.17,0:20:17.39,Default,,0000,0000,0000,,the Five and eight, add 5 gives\Nme 13 again. Take the 10 away
Dialogue: 0,0:20:17.39,0:20:19.63,Default,,0000,0000,0000,,and I end up with three.
Dialogue: 0,0:20:20.50,0:20:24.24,Default,,0000,0000,0000,,So there we have a magicians\Nmemory trick. Now you can
Dialogue: 0,0:20:24.24,0:20:28.32,Default,,0000,0000,0000,,obviously make it as easy as\Ncomplicated as you like for your
Dialogue: 0,0:20:28.32,0:20:31.38,Default,,0000,0000,0000,,audience, so you can choose\Nwhatever formula you want.
Dialogue: 0,0:20:32.48,0:20:34.85,Default,,0000,0000,0000,,And delight your audience.
Dialogue: 0,0:20:36.04,0:20:37.62,Default,,0000,0000,0000,,So to summarize.
Dialogue: 0,0:20:38.23,0:20:39.86,Default,,0000,0000,0000,,Working with formerly.
Dialogue: 0,0:20:40.52,0:20:45.07,Default,,0000,0000,0000,,What you do is substitute\Nnumbers in instead of the
Dialogue: 0,0:20:45.07,0:20:49.62,Default,,0000,0000,0000,,letters and do the calculation.\NBut remember the order of
Dialogue: 0,0:20:49.62,0:20:54.17,Default,,0000,0000,0000,,operations so that you are\Ncorrect with your final answer.
Dialogue: 0,0:20:54.92,0:20:55.88,Default,,0000,0000,0000,,And that's all you do.