The lower and upper fixed points marked on a Mercury-in-glass thermometer are 210mm apart. The end of the mercury column in the tube is 49mm above the lower fixed point in a room. What is the temperature of the room in degrees Celsius? 

lilysparkles

4 years ago

This should be 49-0/210-0=theta-0/100-0

Instead of 49-0/210-0=theta-0/100-theta

Note: 100-0 not 100-theta

Myschool Abby

5 years ago

Thanks for your observation. We have filled in the missing value.

Kluzy

5 years ago

49 is not given in the question but why is it used in the answer segment?

Adeogo26

2 years ago

Please where did 100 come from?

NsibietAbasi06

4 months ago

please a clearer explanation

Icecold10x

2 months ago

where did they get 100 from

Arushi16

2 months ago

FIRST METHOD
Draw your thermometer to make it easier to understand;

----100*C```````----- 210mm
I``````````````I
I``````````````I
I``````````````I
I x________________I 49mm
I``````````````I
----0*C`````````----- 0mm

(X-0) over (100-0) = (49-0) over (210-0)
X over 100 = 49 over 210
cross multiply
210X = 4900
X = 23.3*C


SECOND METHOD
{\} = t over T
where; {\} is the temperature of the room
t is rise above fixed point (49mm)
T is the distance between fixed point (210)
so; {\} = 49 divided by 210
=23.3*C