1
The positively charged central part of an atom
2
The study of heat and its transformation to and from other forms of energy
4
The path of an object as it moves around another object in space
6
The distance from the center of a circle to any point on its circumference
7
A positively charged subatomic particle found in the nucleus of an atom
9
The force exerted per unit area
10
The smallest unit of a chemical compound that retains the chemical properties of that compound
13
A process by which plants use sunlight to synthesize foods with the help of chlorophyll
14
A fundamental force of nature responsible for the structure of atomic nuclei
15
The smallest constituent unit of ordinary matter that has the properties of a chemical element
17
The measure of the amount of space an object occupies
19
The ratio of the length of the opposite side to the length of the hypotenuse in a right-angled triangle
21
A large body of ice moving slowly down a slope or valley
22
A quadrilateral with opposite sides parallel
23
The outermost layer of Earth’s atmosphere
24
A substance that speeds up a chemical reaction without being consumed
27
The branch of mathematics dealing with shapes, sizes, and properties of space
28
The energy possessed by a body by virtue of its motion
31
The smallest structural and functional unit of an organism
33
A polymer of amino acids, essential for all living organisms
36
A system of stars, gas, and dust held together by gravitational attraction
39
The amount of matter in an object, commonly measured in grams or kilograms