"How much I know about Physics": HTML5 Crossword

Across

4. In Physics the phenomenon in which an object changes its position over time (6)
5. A quantity that has both magnitude and direction. It is usually represented by an arrow (6)
7. A unit of length that is one of the seven base SI units (5)
10. Stated facts which have been deduced and derived based on empirical observation (12)
12. The opposite of acceleration. The velocity is dropping compared to the initial one (12)
14. It is defined as the motion, wherein the velocity of the body travelling in a straight line remains the same (13)
15. The natural force that causes things to fall toward the Earth (7)

Down

1. A collection of matter within a defined contiguous boundary in three-dimensional space (6)
2. It is the property of a mathematical relationship or function that can be graphically represented as a straight line (9)
3. Any interaction that changes the motion of an object (5)
6. The active acquisition of information from a primary source eg. Perception and recording of data via the use of scientific instruments (11)
8. A vector quality that is defined as the rate at which an object changes its velocity increasing it (12)
9. The property of the body that determines the body’s acceleration under the influence of a given force (4)
11. The speed at which something moves in one direction (8)
13. The opposite of linearity (5)