Precautions for using physical balance

The physical balance is a commonly used teaching instrument with the advantages of flexible use, accurate measurement, easy maintenance, and durability. It is widely used in colleges and universities, biology, medicine, scientific research and other fields. If you are not careful when using the physical balance, it is easy to cause damage to the physical balance. Today, the editor will introduce the precautions for the use of the physical balance, hoping to help everyone.

Precautions for using physical balance:

1. Pay attention to protecting the blade of the balance. The physical balance is a relatively precise instrument. When using it, pay special attention to protecting its three blades. Generally speaking, the beam should be raised only when the balance is close to balance. Therefore, before weighing an object, you should weigh it with your hand to estimate its mass to prevent it from exceeding the balance's capacity. Put a weight of equivalent mass in the right pan before raising the beam. When adjusting the balance beam balance, the adjustment of the balance screw, adding and subtracting weights during weighing, etc. should all be done under the brake of the balance. Turn the handwheel and raise the beam gently. When the beam is slightly raised, gently lower it immediately if you see it is unbalanced. There is no need to raise the beam completely to the top to observe whether it is balanced. The object to be measured and the weight are placed in the middle of the pan.

2. Do not touch the balance with your hands when using it, and do not place wet objects or chemicals directly on the balance pan. The weights can only be picked up with tweezers, not with your hands, and should be put back into the weight box in time after use.

3. After using the balance, the blade and the blade bearing should be separated. The parts of each balance cannot be interchanged. The balance should be stored in a dry and clean place after use. 4. After weighing, check whether the beam has fallen, whether the position of the beam and the hanging ears is normal, and whether the weights are placed in order, so that the balance always remains in normal condition.

Students are prone to making various mistakes or improper operations when using a balance. In addition to violating the above precautions, there are also the following: moving an adjusted balance during use; not placing the cursor at the zero mark when balancing; not knowing that the cursor can only be used when the balance is unbalanced even after the smallest weight is placed on it; the order of adding weights is not large first and small later, but placing a large weight close to the mass of the object, and then adding (or replacing) a small weight when the balance is unbalanced; collecting the weights first and then recording the data after weighing the object; some even start weighing without hanging the hanging plate on the knife edges on both sides or start weighing without adjusting the balance, etc. These should all be corrected in teaching.