User's Manual

ManualsBrandsPASCO Specialty & Mfg. ManualsCrib ToyPASCO Specialty & Mfg. Parallel Spring Bracket ME-6844

Instruction Sheet

012-09843A

800-772-8700 www.pasco.com

Introduction

The Parallel Spring Bracket allows springs to be combined in

series and parallel. Masses can be hung in offset positions to

compensate for springs of different strengths.

The Parallel Spring Bracket is ideal for:

• exploring how spring constants add when springs are

arranged in series or in parallel,

• demonstrating the analogy between combinations of springs

and combinations of capacitors, and

• exploring torque acting on the hook bar by placement of the

mass and springs at different positions.

Included Equipment Part Number

Suspension Bracket

Parallel Hook Bar

ME-6844

Thumbscrews (2 pieces) 617-016

Additional Equipment Recommended

Series/Parallel Spring Set ME-6842

Equal Length Spring Set ME-8970

Hooked Mass Set SE-8759

Large Table Clamp ME-9472

45 cm Rod ME-8736

Meter Stick SE-8695

Parallel Spring Bracket

ME-6844

Summary of content (4 pages)

PAGE 1
I n s tr u c t i o n S he e t ® 012-09843A Parallel Spring Bracket ME-6844 Included Equipment Part Number Introduction ME-6844 The Parallel Spring Bracket allows springs to be combined in series and parallel. Masses can be hung in offset positions to compensate for springs of different strengths.
PAGE 2
P a r a l le l S p r in g B r a c k e t Set-up ME - 6 8 4 4 Three Parallel 1. Assemble the suspension bracket, a large table clamp and a rod as illustrated. The table clamp (rather than a base) and a relatively short rod are recommended for maximum stability. 2. Hang any combination of springs from the suspension bracket. 3. Attach the parallel hook bar to the bottom of the spring combination. 4. Hook a mass onto the notched slot of the parallel hook bar.
PAGE 3
P a r a l le l S p r in g B r a c k e t Parallel Springs of Different Length A long spring from the Equal Length Spring Set and a short spring from the Series/Parallel Spring Set are combined in parallel. Both springs have the same spring constant (40 N/m). The initial mass is placed off-center to make the hook bar level; however addition mass is added to the center to stretch both springs equally. When the system oscillates, the hook bar rocks.
PAGE 4
P a r a l le l S p r in g B r a c k e t (eq. 4) F net = F s1 + F s2 – mg = 0 The axis about which the torques are measured is chosen to be at the “0 cm” mark. Spring #1 is attached at the axis, therefore its torque is zero. The net torque is ME - 6 8 4 4 Storage To keep the bracket and hook bar together when not in use, clamp the hook bar under the thumbscrews as illustrated. τ net = rs2 F s2 – r m mg = 0 (eq. 5) Solving for F s2 yields: rm F s2 = ------ mg r s2 (eq.