# Newton Lifts

#### Abstract

A student stands on a scale in a life. The scale reading increases or decreases as the life accelerates upward or downward.

#### Portable

Yes – if you have access to a lift you can just borrow our Newton scales, or even use as standard bathroom scale that unfortunately reads in kg.

#### Principles Illustrated

Apparent weight in an accelerated reference frame. The scale reads higher as the lift accelerates upward and then returns to normal as the lift rises at constant velocity. Similarly, the scale reads lower as the scale accelerates downward, and then returns to normal as the scale falls at constant velocity.

#### NCEA & Science Curriculum

SCI 1.1, PHYS 2.4

#### Instructions

A student stands on the scale in a lift. As the lift accelerates upward the reading increases. As the lift accelerates downward the reading decreases. As the lift moves at constant velocity — up, down, or not at all — the scale reads as it does outside the lift.

This demo is not portable unless you have access to a lift.

#### Safety

Individual teachers are responsible for safety in their own classes. Even familiar demonstrations should be practised and safety-checked by individual teachers before they are used in a classroom.