IMO Practice Test — Synthetic Fibres and Plastics
6 Questions • 15 min • Olympiad level
15:00
Question 1 of 6
A nylon thread can be stronger than a steel wire of the same thickness. This makes nylon especially suitable for:
Climbing ropes and seat belts
Window glass
Cooking food
Electric wires' metal core
Explanation: Nylon's great strength suits ropes, parachutes and seat belts.
Question 2 of 6
Terycot is made by mixing two fibres. They are:
Terylene (polyester) and cotton
Nylon and wool
Rayon and silk
Acrylic and jute
Explanation: Terycot is a blend of polyester (Terylene) and cotton, combining their qualities.
Question 3 of 6
Why are the handles of cooking utensils often made of thermosetting plastic rather than metal?
The plastic is a poor conductor of heat, so the handle stays cool
The plastic conducts heat better
Metal is cheaper
Plastic melts easily on heating
Explanation: Thermosetting plastics like bakelite are poor heat conductors, so handles do not get hot.
Question 4 of 6
Firefighters' suits are sometimes coated with melamine because melamine:
Resists fire and heat
Burns quickly
Dissolves in water
Conducts electricity
Explanation: Melamine resists fire and heat, so it is used on firefighters' uniforms.
Question 5 of 6
Synthetic clothes can be dangerous near a flame because they:
Melt and stick to the skin
Turn to ash harmlessly
Put out the fire
Become stronger
Explanation: Synthetic fibres melt and can stick to the body, which is why cotton is safer near fire.
Question 6 of 6
Why is it better to carry a cloth or jute bag instead of a plastic bag?
Cloth and jute are biodegradable and reusable
Plastic bags are biodegradable
Cloth pollutes more
Jute is non-renewable
Explanation: Cloth and jute are natural, biodegradable and reusable, reducing plastic waste.