Question

C) One day on the lake we went between the dots. The following times were measured. 240 seconds, 20 minutes, 10.6 minutes and 45 minutes. I started at 10am, what time did I pass the last dot? And how long did it take?

Uppgift 2

A) How many dl of sugar do I get if I collect everything in a jar. The small bowl has ¾ dl sugar and between the bowl has 3/8 dl sugar?

B) Then mix 1.5 dl of liquid. 12% was water, 48% was milk and 40% was cream. How many dl did I take from each part?

Uppgift 3

A) What speed do I keep if I cut a distance of 20km in 15 minutes?

B) To calculate the effect in a liquid cooler, I used the following method Effect = flow / h * energy content of the liquid * temperature difference.

20 l / min, 4.18kJ / kg * K, 10K. How big is it?

C) To calculate the resistance, I used the following method:

1 / R = 1 / R1 + 1 / R2 + 1 / R3. R1 = 4, R2 = 3, R3 = 4 What is the resistance R?

D) What will be the current I if U = I * R and U = 12Volt

E) Calculate the power P = U * I

Answer 1

C.

Here the total time to pass last dot is given as,

T = 4+20 +10.6 +45 min = 79.6 minutes = 1.32666hrs

So that time i passed last dot will be 10 + 1.3266 = 11.3266 am.

And it will take total 1.32666 hrs .

Uppgift 2

A. Total dl of sugar in the jar will be = 3/4 + 3/8 = 9/8 dl

B.Here ,

Total mix = 1.5 dl of liquid.

12% was water then its dl = 12×1.5/100= 0.18 dl

48% was milk so its dl = 48×1.5/100 = 0.72 dl

and 40% was cream so its dl = 40×1.5 /100 = 0.60 dl

Uppgift 3

A. Speed = 20 ×1000/ 15 ×60 = 22.222 m/s

B.Here the formula given as,

Effect = flow / h * energy content of the liquid * temperature difference

Flow = 20 l/ min = 1200 l per hour

4.18kJ / kg * K = 4180 J/kg K

Temperature= 10K.

On substitution of values we will get,

Effect = 50,160,000

C. Here given that,

1 / R = 1 / R1 + 1 / R2 + 1 / R3 = 0.8333 where,

R1 = 4, R2 = 3, R3 = 4

So that R = 1.2 ohm

D. I = U/R = 12/ 1.2 = 10 A

E. P = UI = 12 ×10 = 120 Watts.