Learning is fun: Spring Balance

Spring balance is a type of weighing machine. Weighing machines and scales are used to weigh quantities. A spring balance contains a spring (stretching material) that stretches in proportion to the weight of the object being weighed. The spring moves a pointer on a graduated scale.

Things Required

Spring (or a stretchable material like a flexible rubber band), a hook , a pointer, thread/rope, container, a strip of paper, objects of known weight.

Step 1 : Tightly secure one end of the spring to the hook. Fix a pointer horizontally to the other end of the spring. Tie a long rope to the same end of the spring.

Step 2 : Make 4 holes to the container and tie equal length ropes to each hole. Then knot all the ropes together and secure it to the free end of the rope hanging from the spring.

Step 3 : Hang your set-up freely from a height with the help of the hook. Stick the strip of paper to the wall or to the hook.

Step 4 : Take a pen and mark 0g on the paper strip when there are no weights in the container. Now add known weights (50g,100g,200g etc) to the container one by one. As weights are added the spring stretches and the pointer moves down the scale indicating the weights on the paper strip.