**Torque**

Larry L. Smart Helen Hefferan Elem.School

4409 W. Wilcox St.

Chicago IL 60624

(312)534-6129

**Objectives**:

This assignment will be for 6th grade students. The main objective of this mini-

teach is to show the difference between Work and Torque, in relationship to

Force and Distance.

**Materials Needed**:

1. A Jensen balance bar with ten 50 gram weights.

2. A Torque bar with a 500g weight.

3. A wooden wheel with four nuts and bolts drilled in it.

**Strategy**:

1. The students are given the weight and distance on the left side of the

balance bar and asked where to place another weight in order to balance

the bar.

2. Give the student the torque bar and a weight. The teacher moves the

weights to different positions on the bar. Record the student's

observation.

3. Have some students use a small wrench to loosen 2 bolts and other students

use a large wrench to loosen 2 bolts. Record the observations. Discuss

the ratio between amount of force and the length of the wrench. (The

longer the wrench, the less force required to loosen the bolts.)

**Performance Assessment**:

Assessment will be based on the following:

1. The teacher will put a weight on the balance bar at a specific location

and give the student a weight. The student will be asked to balance the

bar by choosing the appropriate location on the bar.

2. Torque worksheet with the formula, (T = D x F).

3. The student will explain why the larger wrench loosens the nut with less

force than the smaller wrench.

**Conclusions**:

1. The torque on both sides of a Jensen Arm, when the bar is balanced, will

be equal.

2. The bar will require more force in order to hold it horizontally as the

weight is moved away from the handle. (It will feel "heavier", but it is

the SAME MASS, only in a different location. It requires MORE FORCE, but

is no heavier.)

3. The larger wrench will remove the nuts with less force than the smaller

wrench. (D x f = d x F) (The large wrench, a BIG DISTANCE times a small

force is equal to a small distance times a BIG FORCE, the small wrench.)

4. The difference between torque and work is the concept of rotation. Torque

is work (distance times force) which causes rotation.

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