Download First Diploma in Engineering Applied Electrical and Mechanical S

First Diploma in Engineering
Applied Electrical and Mechanical
Science for Technicians
Assessment booklet
Don’t forget that when submitting work you must declare which outcome you are
claiming. (P1, M3, D2,for example)
Don’t forget to put your name on all submitted work.
When requested, work must be submitted with the assignment facing sheet, signed.
Make sure that you understand the work you have submitted. You may be asked
questions upon submission.
Work which is not reasonably presented might not be accepted.
P1 define parameters of direct current electricity and magnetic fields
Define the following terms. Give the unit of measurement for each of these
parameters:a) Electric charge
b) Electric current
c) Electromotive force
d) Electrical resistance
e) Magnetic flux
f) Magnetic flux density
g) Electric power
P2 determine total resistance, potential difference and current in series and parallel
dc circuits from given data
a) See figure 1. Calculate:
i) The current flowing from the supply
ii) The potential difference across each resistance.
7Ω
5Ω
Figure 1.
4Ω
b) See figure2. If R1 = R2 = R3 = 7Ω Calculate:
i) The current flowing from the supply
ii) The potential difference across each resistance
iii) The current flowing through each resistance.
Figure 2.
P3 define parameters of static and dynamic mechanical systems
Define the following parameters of static and dynamic mechanical systems:
a) mass
b) weight
c) force
d) moment of a force
e) density
f) relative density
g) displacement
h) velocity
i) acceleration
j) work
k) power.
P4 (See also M2) determine the resultant and equilibrant of a system of concurrent
coplanar forces from given data
Determine the resultant and the equilibrant of the system of force vectors shown here.
The angles are:a = 60°
b = 30°
c = 45°
d = 45°
P5 determine the uniform acceleration/retardation of a body from given data
A commuter train starts from rest at a station and is uniformly accelerated for 2
minutes, during which it travels a distance of 6 km. It then continues at a steady
velocity for a further 10 km before being uniformly retarded to rest at the next station
over a distance of 5 km.
Calculate:
(a) the uniform acceleration during the first 2 minutes of the journey.
(b) the velocity at the end of the acceleration period.
(c) the time for which the train is travelling at a steady velocity.
(d) the retardation as the train is coming to rest.
(e) the total time taken in travelling between the stations.
P6 determine the pressure at depth in a fluid from given data
A submarine dives to a depth of 95m. What is the absolute pressure exerted on the
submarine? Use 1020kg/m³ for the density of the water, and 100 x 103 Pa for
atmospheric pressure.
M1 determine the force on a current carrying conductor situated in a magnetic field
from given data
The dimensions of the conductors in the motor shown in the diagram are:
ab = cd = 30cm
bc = 20cm
The magnetic flux density, B = 0.3 T
If the current through the wire is 0.3A, calculate the force on section:
(a) ab of the conductor (stating the direction of the force)
(b) bc of the conductor
Calculate the moment of the force on ab, about the centre of the coil.
M2 describe the conditions required for the static equilibrium of a body
See also P4.
D1 Describe the basic construction, operation and use of an electromagnetic coil.
Electromagnetic coils are put to many different uses, for example in
transformers, relays, microphones and loudspeakers. Many uses for a coil have
been discussed during the course, and you need to write a detailed account of
one example.
Your submission must be all your own work, and should demonstrate that you
understand how the component is put together, what materials are used, how it
works, and to what uses it can be put. Including your own drawings and
diagrams would help to show your own knowledge of the subject.
D2 determine the work done and the power dissipated in moving a body of
given mass along a horizontal surface at a uniform velocity, given the value
of the coefficient of kinetic friction between the surfaces
An electric truck pulls a girder of mass 450 kg along a horizontal floor at a steady speed
of 0.5 msˉ¹ for a period of 12 seconds. The coefficient of kinetic friction between the
girder and the floor is 0.4 and the towrope is parallel to the floor.
Calculate:
(a) the distance travelled
(b) the force exerted by the truck
(c) the work done
(d) the power dissipated.