DesEng Practice 3

An example of a 'wastage' method is...

• Drilling a hole in a block of wood

• Bending a sheet of metal with the 3-in-1

• Fused Deposition Modelling with a 3D printer

• Welding two plates of steel together

 $\times10^6$   is...

• Kilo

• Mega

• Giga

• Terra

• Peta

Which of these will provide the potential difference between ground and an analogue input pin on a PIC?

•  $V_2=V_t\times\left(\frac{R_2}{R_1+R_2}\right)$  

•  $V_1=V_t\times\left(\frac{R_1}{R_1+R_2}\right)$  

•  $V_2=V_t\times\left(\frac{R_1}{R_1+R_2}\right)$  

•  $V_1=V_t\times\left(\frac{R_2}{R_1+R_2}\right)$  

When a metal rod is stretched, usually one section of the sample will thin in the middle prior to the sample failing. This is referred to as...

• Necking

• Thinning

• Smiling

• Ultimate tensile strength

Which of these would be an application for PWM?

• Setting up a monostable circuit

• Protecting a solenoid from back-EMF

• Dimming an LED

• Reducing the ripple effect on an AC power supply

An LED is connected to a PIC output pin. What would be needed to replace this with a 230V (AC) signal lamp?

• Opto-Isolator

• SPST relay

• MOSFET

• NPN Transistor

• PNP Transistor

A resistor...

• Reduces the flow of current

• Reduces the voltage

• Reduces power

• Creates back-EMF

An example of Quality Assurance would be

• Installing a fresh drill bit prior to drilling out a PCB

• Checking that no holes have been missed after drilling a PCB

• Wearing goggles while drilling the holes in a PCB

An example of Quality Control would be

• Installing a fresh drill bit prior to drilling out a PCB

• Checking that no holes have been missed after drilling a PCB

• Wearing goggles while drilling the holes in a PCB

An advantage of using a planetary (epicyclic) gear system is...

• Reduced complexity to design

• High gear ratios can be produced in a small space

• Reduced lubrication requirements

• Easily accessible for maintenance