Câu hỏi:

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 33 to 42

Magnets

A solid object that has the power to attract iron and some metals is called a magnet. It does this through its magnetic field, a region of force surrounding it. The (33) _____ the magnet, the more intense is the field.

Objects that are attracted to the magnet feel a force (34) _____ as “magnetism” when they are inside the magnetic field. This magnetic force can pass (35) _____ some materials. Even a weak magnet will attract a pin to the other side of a (36) ______ of paper, for example.

 Magnets come in (37) ______ shapes. A familiar one is the curved horseshoes magnet. There are also bar magnets in the form (38) _____ disc or a stubby cylinder. Every magnet has (39) ______ poles, called north and south, at opposite ends of it: at the two ends of a horseshoes magnet, for example, or on the two sides of a disc.

Powerful magnets can be (40) _______ by passing an electric current through wire coiled around a piece of iron. The (41) _____ is called and electromagnet. Magnets are (42) ______ in many household and everyday devices. They are also commonly used in industrial machinery, usually in the form of electromagnets.Question 37