Physics Quiz for Grade 1 - Display Devices

What color light does an LED emit?

• It emits light in all colors at once

• It emits light in the color of the device it is installed in

• It emits light in the color of the power source

• It emits light in a specific color based on the material used.

What is the shape of an LED?

• Large and triangular

• Oval and flat

• Small, round or rectangular

• Irregular and hexagonal

How does an LED work?

• An LED emits heat when an electric current passes through it.

• An LED emits light when an electric current passes through it.

• An LED emits sound when an electric current passes through it.

• An LED emits water when an electric current passes through it.

Where can LEDs be used?

• In kitchen appliances

• In clothing and fashion accessories

• In electronic displays, indicator lights, and automotive lighting

• In pet care products

What are the properties of laser diodes?

• Emitting incoherent light, large size, low efficiency

• Emitting non-coherent light, medium size, moderate efficiency

• Emitting coherent light, compact size, high efficiency

• Emitting scattered light, small size, low efficiency

How does a laser diode work?

• A laser diode works by using a liquid crystal display to emit light

• A laser diode works by using a vacuum tube to generate light

• A laser diode works by using a magnetic field to produce light

• A laser diode uses a semiconductor to produce coherent light through stimulated emission.