The diagram shows a ray of light reflected at a plane mirror.
Which pair of the angle of incidence and angle of reflection is correct?
| Angle of incidence | Angle of reflection | |
| A | 30° | 30° |
| B | 30° | 60° |
| C | 60° | 30° |
| D | 60° | 60° |
Fill in the blanks by choosing an appropriate option. The loudness of sound depends on its _(i)_ . The _(ii)_ determines the pitch of a sound. A bird makes a _(iii)_ sound where as a lion makes a _(iv)_ sound. Usually voice of a woman has a _(v)_ frequency than that of a man.
| (i) | (ii) | (iii) | (iv) | (v) | |
|---|---|---|---|---|---|
| A | Amplitude | Frequency | Low-piched | High-piched | Lower |
| B | Pitch | Frequency | Low-piched | High-piched | Lower |
| C | Amplitude | Frequency | High-piched | Low-piched | Higher |
| D | Frequency | Pitch | High-piched | Low-piched | Higher |
