Quiz Preparation – UMD Racing e.V.

Quiz „General Engineering“

1 / 10

1. Your team is the first car at the design event during FSN2022 and it’s quite cold for this time of the year, 12 degrees C. To impress the judges, you decide to make some tea for them. What is the minimum required time to prepare the tea, knowing that you have to boil 4 tea cups of 370ml each and you have an electrical heater with a power of 500W. Give your answer to the nearest whole number in secs.

p2 = p1 * (V1/V2)^gamma
gamma= 1.4

2 / 10

2. An air as an ideal gas expands adiabatic from a volume of V1 = 1,00l with its pressure of p1 = 10^5 Pa to 1/10 of its original pressure. What volume V2 (in litres) does the gas reach after it’s expansion? Round to two decimal places

3 / 10

3. Calculate the force Fc working at point C. Give answer in kN rounded to one decimal place.

Forces at point A: Rax = 3kN, Ray = 9kN, Ma = 10kN/m

4 / 10

4. A lorry contains an engine with a power of 0.255 W. The lorry drives for 51 s. Calculate the energy transferred in Joules and round to one decimal places.

5 / 10

5. Unit: kg/(m^3), to decimal number seperated by: . (exp. 15.3), write only the number in the field below

6 / 10

6. In a gas pipe, the gas pressure pG is measured using a U-tube manometer connected at the bottom. Above the meniscus of the measuring liquid (mercury with density ρQ) on the gas side, there is a column of water with height h₂ and density ρW.
Question:
What negative pressure △pU (vacuum) exists in the pipe compared to the external pressure p₀?

Result in Pa, two decimal numbers seperated by a point (exp. 15.3). Do not put the Unit in the field below.

7 / 10

A metal piece heated to

θ_1,M=1000∘C

with a mass of

M_M=6.5 kg

was cooled in a completely heat-insulated iron container filled with water. The mass of the water in the container is

M_W=10 kg

and the mass of the container is

M_B=2 kg.

The initial temperatures of the water and the container were the same and amounted to

θ_1,W=10∘C

. After complete thermal equilibrium between the immersed metal piece, the water, and the container, a temperature of

was established.
What is the average specific heat capacity of the metal piece

c

in the temperature range between

and

Input the result in kJ/(kg*K), round to 3 decimal numbers sperated by a point (example: 0.136).

8 / 10

8. A team is in the process of validating the compliance of the shoulder harness bar used in their car. Choose the part in which their configuration is incompliant:

a. The attachments are positioned 220 mm apart, measured center to center, and have a thickness of 1.7 mm

b. The bar is bent (not straight) and the team uses an analysis method of inducing 7kN to each attachment in the horizontal plane to prove compliance

c. From the driver’s shoulders rearwards to the mounting point or structural guide, the shoulder harness is 8° above the horizontal

d. The steel tube has a thickness of 2 mm, and a 0.26% in carbon and 1.7% manganese content

9 / 10

An air stream

dot{M}_L = 5.5 kg/s,

cp_L=1 kJ/(kgK)

is to be heated in a plate heat exchanger from

θ_L′=20∘C

θ_L′′=150∘C

. For this purpose, a flue gas stream

dot{M}_R = 7.22

cp_R=1.1 kJ/(kgK)

with a temperature of

θ_R′=300∘C

is available. The overall heat transfer coefficient is

W/(m^2*K)

.
What is the required heating surface AAA if the fluid streams are arranged in counterflow?

a. 328,1 m^2

b. 281,7 m^2

c. 314,12 m^2

10 / 10

10. For a horizontally positioned, non-insulated steam pipe with a length of l=3 m and a diameter of d_a=0.1 the convective heat loss Q_point is to be calculated. The temperature of the surrounding air is θ_f=30∘C and that of the outer wall surface is θ_w=170∘C.

Input the result in kW and round to two decimal numbers seperated by a point without thr unit (example: 145.35)

Dein Ergebnis ist

Die durchschnittliche Punktzahl beträgt 0%