Series:

Welcome Books: Simple Machines

6 total works

Cover of What Is a Screw?

What Is a Screw?

by Lloyd G Douglas

Published 1 September 2002

Cover of What Is a Lever?

What Is a Lever?

by Lloyd G Douglas

Published December 2003

Cover of Welcome Books- What is a Pulley? Simple Machines

Cover of What Is a Plane?

What Is a Plane?

by Lloyd G Douglas

Published December 2003

Cover of What Is a Wedge?

What Is a Wedge?

by Lloyd G Douglas

Published 2 December 2005

Cover of What Is a Wheel and Axle?

What Is a Wheel and Axle?

by Lloyd G Douglas

Published 1 September 2002