Across
1
Push or pull on an object
5
Unit of force
6
Unit of electric potential
7
Particle of light
8
Biological catalyst
9
Curved glass that refracts light
Down
2
Path of a planet around the sun
3
Reddish electrical conductor
4
Blocking of light by a celestial body
10
Element found in all living things
11
Absolute temperature scale unit
12
Nerve cell in the brain