Electric Charge
4 marks · EasyAn inkjet printer uses electrostatics to direct charged ink droplets onto paper. At the same time, a student is warned not to touch computer parts directly because of static electricity.
Describe how static electricity is used to control where ink lands in an inkjet printer.
Explain one way static electricity could damage computer components.
State one precaution workers can take to avoid damage due to static electricity when handling electronics.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) Ink drops are given a charge and pass between charged plates, which direct the drops to the correct position using electrostatic forces.
(b) A static discharge (spark) could damage or destroy sensitive electronic components.
(c) Wear an earthed wrist strap, or work on an earthed surface to discharge static safely.
Show mark scheme and worked solution
Marking points
M1 (a) · 1 mark · Mentions charging ink drops or plates create electric field.
A1 (a) · 1 mark · States deflection of ink drops directs ink to precise spots on the paper.
B1 (b) · 1 mark · States static spark can damage/destroy computer parts.
B2 (c) · 1 mark · Describes a suitable anti-static precaution (e.g., earthed wrist strap).
Worked solution
a) Ink droplets are given a charge and shot between two plates that are also charged. By changing the voltage on the plates, the droplets are pulled in different directions, making precise images on paper.
b) A sudden discharge of static electricity could cause a spark that breaks or damages sensitive electronic parts.
c) A worker can wear an earthed wrist strap to safely remove charge and prevent sparks when handling electronics.