Question
Choose just one answer.a,b,cor d. A luminous object: a) reflects light b) refracts light c) gives off light d) diffracts light (1 mark) Which of these is an example of a transparent object? a) a brick b) a pane of glass c) a piece of wood d) a mirror (1 mark) We see lightning before we hear the thunder because: a) light waves are stronger than sound waves b) sound travels faster than light c) light travels faster than sound d) sound waves are stronger than light waves (1 mark) Answer all parts of all questions. 1 Fill in the missing words. We can see through a pane of glass because glass is a __ material We cannot see through a sheet of steel because steel is an __ material If we place an __ object in front of a source of light we can create a ........................ __ An object that emits light like a __ is called a __ object.We see __ __ objects because of the __ they reflect. Shadows have the same __ as the objects that create them.This suggests that __ travels in __ Light waves travel much __ than sound waves.This is why we always see lightning before we __ the __ (14 marks) 4 Arayof light strikes the surface of a plane mirror with an angle of incidence of 60^circ What is its angle of reflection? a) 30^circ b) 10^circ C) 90^circ d) 60^circ (1 mark) 5 An optical instrument that contains two mirrors and can be used to look over high walls is called a: a) kaleidoscope b) telescope c) microscope d) periscope (1 mark) Score ... 15
Answer
4.4
(263 Votes)
Marshall
Elite · Tutor for 8 years
Answer
The first question inquires about the property of a luminous object. Physically and logically, a luminous object inherently produces or emits light, which makes it visually noticeable in darkness.✔ So, the answer to the first question is c) gives off light.Second question asks for an example of a transparent object. A transparent substance or object allows visible light through it, enabling observers to distinctly view the object on the other side. ✔ Thus, the answer to the second question is b) a pane of glass.The third question explains why we observe a flash of lightning prior to hearing the associated thunder. This discrepancy is due to the fact that light travels at a significantly faster pace than sound does.✔ Therefore the answer to the third question is c) light travels faster than sound.The fourth question is rooted in the study of reflection in physics, under optics. When a ray of light strikes a plain mirror, it is reflected back maintaining the same angle as it was projected.✔ Thus, the answer to the fourth question is d)
.The fifth question demands the identification of an instrument that employs two mirrors and can facilitate vision above tall obstructions. Given the option the most correct is an optomechanical device, namely a periscope. ✔ Thus, answer to the fifth question is d) periscope.Moving forward to the fill-in-the-blanks portion, the blanks can be completed as follows:•Transparent & Opaque: We can see through a pane of glass because glass is a 'transparent' material. We cannot see through a sheet of steel because steel is an 'opaque' material.•Luminous & Shape: If we place a 'Luminous' object in front of a source of light we can create a ' Shape', An object that emits light can be called a 'Luminous' object. We see 'Opaqe-Object' objects because of the 'Light' they reflect.•Shape & straight: Shadows have the same 'Shape' as the objects that create them. This suggests that 'Light' travels in 'Straight lines`.•Faster: Light wares travel much 'Faster' than sound waves.•Hear & Thunder. This is why we always see lightning before we 'hear' the 'Thunder'.