• 4 months ago
This is question related to sexagesimal system Ex6.1 question 4
Transcript
00:00This is question number 4 of exercise 6.1.
00:04We have to convert angles in degrees, minutes and seconds.
00:09You have 60.125 degrees, now what will you do in this?
00:14In sexadecimal system, we basically eliminate decimal point.
00:19How?
00:20You have 60 degrees, you separate them.
00:23Which is your decimal part, 0.125 degrees.
00:28Now I will convert this into minutes by multiplying by 60.
00:33When I am multiplying this by 60, you get the answer as 7.5.
00:44Now, again you have decimal point.
00:48So, I will write 60 degrees, 7 minutes.
00:52Now, multiply 0.5 by 60 again.
00:57So, it will be converted into seconds.
01:00Finally, the answer will be 60 degrees, 7 minutes.
01:04When we multiply 0.5 by 60, you will get 30 seconds.
01:11Means, 60.125 degrees is equal to 60 degrees, 7 minutes and 30 seconds.
01:21In the second part, you have 135.375 seconds.
01:26You have to change it into degrees, minutes and seconds.
01:30In one degree, there are 3600 seconds.
01:35Now, what will we do?
01:36First, we will convert all the values into degrees.
01:41When we divide it,
01:46Divide 135.375 by 3600.
01:54So, the value you are getting in degrees is 0.0377 degrees.
02:01Now, you see that everything is in decimal.
02:04So, what will you do?
02:06You will separate 0 degrees from this.
02:09And you will multiply 0.0377 by 60 to get minutes.
02:17When you multiply it, you will get 0 degrees plus 2.262 minutes.
02:29Again, you do not need decimal point in sexagesimal system.
02:34So, we will take 0 degrees from this and 2 minutes.
02:38Now, we will multiply 0.262 by 60 to get seconds.
02:47So, it will become 0 degrees plus 2 minutes.
02:50When we multiply it by 60, it will become 15 seconds.
02:54Even after this, if there is any decimal point left, you can ignore it.
03:00In the third part, you have 60.85 minutes.
03:03You have to convert it into degrees.
03:06In one degree, you have 60 minutes.
03:09What will you do first?
03:12First, you divide it.
03:1460.85 divided by 60.
03:18Now, it will convert into degrees in minutes.
03:21And you will get 1.0141.
03:26Calculator is giving you the answer like this.
03:29But you have to take up to 4 decimals in these questions.
03:34So, 1.0141.
03:37What is the rule of rounding off? 1, 2, 3, 4.
03:40We have to ignore all these.
03:42If you want to ignore 5 or more than 5, add 1 here.
03:48So, it will become 1.0142.
03:53You have got the answer in degrees.
03:56Now, you divide 1 degree from this.
03:59And multiply 0.0142 by 60.
04:04So, you will get minutes.
04:06Again, the answer you are getting is 1 degrees plus 0.0852 minutes.
04:16Now, you will see that there is a decimal portion.
04:19It means that you have 1 degree and 0 minutes.
04:24Because it is a decimal portion.
04:26We have not got any integral number here.
04:28So, we will multiply the remaining decimal portion 0.0852 by 60.
04:34So that we can convert it to seconds.
04:36So, 1 degree, 0 minutes.
04:38And when we multiply it by 60, we will get 51 seconds.
04:43And if there is still some decimal portion left, you will simply ignore it.
04:48You have 255.45 degrees.
04:52Very simple question.
04:54Divide 255 degrees.
04:57The decimal portion is 0.45.
05:00Simply multiply it by 60.
05:04It will be converted into minutes.
05:07You will get 255 degrees plus 27 minutes.
05:12Now, we do not have any decimal portion left.
05:15It means that we do not need to go into seconds.
05:18We will combine it and write.
05:20So, you will get 255 degrees plus 27 minutes.
05:24This is the required answer.
05:26Thank you.