1.
What is an advantage of a ratchet and pawl mechanical system?
A.
The teeth allow for rotation in two directions.
B.
It allows for a smooth transmission of movement.
C.
It increases safety in a lifting device for heavy loads.
D.
It is used at high rotational speeds.
(Total 1 mark)
2.
What would be an advantage when using a chain drive system instead of a belt drive system?
A.
Cost
B.
Ease of maintenance
C.
Only suitable when there are long distances between shafts
D.
Can be set at a precise speed of rotation
(Total 1 mark)
3.
The figure below shows a double-winged lever design corkscrew patented by Dominick Rosati
in 1930. The corkscrew is placed over the lip of the bottle and the worm screwed into the cork
so that the wings lift up. When the worm is far enough into the corkscrew, the wings are pushed
down and the cork is lifted out of the bottle. A force of 360 N is required to remove the cork
from the bottle. The Alessi Anna G novelty corkscrew designed by Alessandro Mendini works
on the same principle as the corkscrew in the figure below.
A double-winged lever design corkscrew
[Source: http://en.wikipedia.org/wiki/File:Corkscrew_P1150886.jpg. Image by David Monnaiux.]
IB Questionbank Design Technology
1
(a)
(i)
Identify the class of lever represented by the wing of the corkscrew shown in the
figure above.
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(2)
(ii)
Calculate the force which would need to be applied to the end of each wing of the
corkscrew shown in the figure above to lift the cork out of the bottle.
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(3)
(b)
(i)
Describe how design costs would contribute to the final cost of the Alessi Anna G
corkscrew.
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(2)
(ii)
Describe how the concept of break-even relates to the production of the Alessi
Anna G corkscrew.
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(2)
IB Questionbank Design Technology
2
(c)
(i)
Identify how Alessandro Mendini has managed to balance form with function in
the design of the Alessi Anna G corkscrew.
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(2)
(ii)
Discuss how consumers might use product image, performance and durability at
different stages of the product lifecycle to evaluate the Alessi Anna G corkscrew.
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(9)
(Total 20 marks)
IB Questionbank Design Technology
3
4.
For which lever(s) would the mechanical advantage be less than 1?
A.
I only
B.
II only
C.
III only
D.
I and III
(Total 1 mark)
5.
What type of mechanism is shown in the system below?
[Source: http://www.gessford.com/cobraparts/images/marchshelby.gif]
A.
Gear
B.
Belt
C.
Chain drive
D.
Lever
(Total 1 mark)
6.
(a)
State the unit used to measure torque.
IB Questionbank Design Technology
4
......................................................................................................................................
......................................................................................................................................
(1)
(b)
Explain the relationship between linear motion and rotational motion when riding a
bicycle.
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(3)
(Total 4 marks)
7.
Which cam follower is an example of a knife follower?
(Total 1 mark)
8.
What effect does a linkage have on the motion of components in a mechanical system?
A.
It decreases the speed
IB Questionbank Design Technology
5
B.
It increases the speed
C.
It changes the direction
D.
It changes the type
(Total 1 mark)
9.
What is the left to right order of the following three forces?
[Source: “Forces acting on bridges”
http://library.thinkquest.org/06aug/02102/Forces%20acting%20on%20Bridges.html]
A.
Tension, Compression, Torque
B.
Compression, Tension, Torque
C.
Compression, Torque, Tension
D.
Tension, Torque, Compression
(Total 1 mark)
IB Questionbank Design Technology
6
10.
Choose the missing words to complete the sentence which describes the gears in Figure 3.
This gear system converts _____________ motion into ______________ motion.
Gear system
A.
linear / reciprocal
B.
reciprocal / linear
C.
linear / rotary
D.
rotary / linear
(Total 1 mark)
11.
What is the purpose of a ratchet and pawl system?
A.
Allows rotation in one direction only
B.
Provides a mechanical advantage
C.
Changes motion from oscillating to reciprocating
D.
Maximizes the velocity ratio
(Total 1 mark)
IB Questionbank Design Technology
7
12.
Please read the case study carefully and answer the question.
The diagram below shows the internal workings of a wind turbine that generates electricity.
Wind turns the blades (1) which are connected to a shaft (5) which through a series of gears
drives the generator (7) and produces electricity. The blades turn at about 30 rotations per
minute and the generator needs to turn at least 1500 rotations per minute in order to produce
useful amounts of electricity.
The blades are designed to flex when there are gusts of wind to reduce some of the force on the
tower (15). With a wind gust of 60 kph, the load at the end of the blades is 300 Newtons and the
blades will deflect 100 mm.
Mechanism of a wind turbine
IB Questionbank Design Technology
8
What is the minimum velocity ratio of the gear box (6) in the diagram above to produce
electricity?
A.
1:500
B.
1:50
C.
50:1
D.
3:15
(Total 1 mark)
13.
(a)
Describe a chain drive system.
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(2)
(b)
Describe how a gear system interacts with a chain drive system in a bicycle.
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(2)
(Total 4 marks)
IB Questionbank Design Technology
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14.
What mechanical motion is used with this screwdriver?
A.
Torque
B.
Rotary
C.
Reciprocating
D.
Irregular
(Total 1 mark)
15.
Which mechanism includes a linkage?
A.
TV remote control
B.
Water tap
C.
Foot operated rubbish bin
D.
Frying pan
(Total 1 mark)
IB Questionbank Design Technology
10
16.
Which of the following is an example of a third class lever?
A.
B.
[Image by ZooFari.
http://commons.wikimedia.org/wiki/File:
Scissors_simple.svg?uselang=en-gb]
[Source: Pearson Scott Foresman, donated to the
Wikimedia Foundation]
C.
D.
[Image by aarchiba]
[Image: Markus Hagenlocher]
(Total 1 mark)
IB Questionbank Design Technology
11
17.
Figure 1 shows the Avelo Shimano 6–speed folding bicycle made from a metal alloy frame and
available with 20 inch (50.8 cm) diameter alloy wheels. The seat is adjustable to different
heights. Figure 2 shows the Shimano bicycle folded. Sales of folding bicycles continue to rise
globally.
Figure 1: Shimano bicycle
Figure 2: Shimano bicycle folded
[Source: www.amazon.co.uk]
(a)
(i)
Outline one reason why the bicycle in Figure 1 is designed with an adjustable seat.
(2)
(ii)
Outline one advantage of using a metal alloy for the bicycle frame.
(2)
(b)
(i)
Describe how the gear system of a bicycle interacts with the chain drive system.
(2)
(ii)
Explain how the efficiency of the bicycle as a mechanical system can be calculated.
(3)
(c)
(i)
Describe the type of energy conversion involved in cycling.
(2)
(ii)
Discuss three reasons why the folding bicycle design may contribute to an increase
in the popularity of cycling.
(9)
(Total 20 marks)
IB Questionbank Design Technology
12
18.
What is the velocity ratio for a wheelbarrow if it has to be lifted 300 mm for the load to rise 200
mm?
A.
1.5
B.
2/3
C.
0.5
D.
1:5
(Total 1 mark)
19.
What is an advantage of a belt drive over a chain drive system?
A.
There is less slippage
B.
It adjusts readily to changes in load
C.
It can carry a heavier load
D.
It has a longer product life
(Total 1 mark)
20.
What conversion of motion is done by the pinion-driven mechanism below?
Pinion driven mechanism
A.
Linear to intermittent
B.
Rotary to linear
C.
Rotary to reciprocating
D.
Linear to rotary
(Total 1 mark)
IB Questionbank Design Technology
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