3 rd order lever
yes its a wedge
The air molecules inside the test tube have a higher mobility when heated (they move around more). The collisions between these air molecules create more pressure on the inside of the test tube (force/area, where the force is the result of the increasing collisons and the area is the internal wall of the test tube.) This may result in the pressure inside of the test tube to be greater than the outside atmospheric pressure on the cork (actually atmospheric pressure on the cork and the frictional force on the cork created by the mouth of the test tube). If the internal pressure becomes greater than the external pressure (plus frictional force) the cork will come loose of the test tube.
A test tube is filled with tap water (about 25oC). An ice block is placed in the test tube and is kept at the bottom of the test tube by means of a wire gauze. Next (without delaying too much since the ice block would melt completely!), the test tube is bent and the upper end of the test tube placed in a Bunsen flame. It is found that the water at the upper end boils before the ice block melts. This shows that water is a poor conductor of heat.
A tube!
A vernier caliper
Very simple, place the test tubes in the holder.
Test tube holder
use to hold test tube..
it is a testube holder
Like the function of a beaker; to hold chemicalsA test tube is another useful science equipment used in experiments. A test tube is used:-1. to carry solids or liquids in small quantity.2. to do experiments, such as knowing the nature of the substance poured in it( acidic, basic or neutral) .basically, test tube's function is to carry substances in science labs.
A culture tube or sample tube.
When heating a test tube, you would use a test tube holder. It can also be used to hold/ support pipettes, etc. http://www.answers.com/mt/test-tube-holder
it is use to hold the test tube
You need a test tube holder.
A test tube holder is a device to ...wait for it...hold test tubes ! ;-) Usually a rack or clamp that keeps them upright (& full if in use).
If you are heating a test tube, point it away from yourself and others. If you need to place a test tube into a hot water bath, or take it out of a hot water bath, you need to use a test tube holder and not your unprotected fingers. Do not leave the test tube holder attached to the test tube while it is heating, as this will also heat up the test tube holder. If a test tube breaks, tell your teacher, and clean it up with a broom and dust pan. Don't pick the glass up with your fingers.
No. A ringstand is a stand with a base with a large pole sticking out of it. that you can attach rings to. A wire mesh is usually placed on the ring for setting a beaker to be heated. A test tube clamp can be attached to the ring stand to hold a test tube, for say, heating it in a hot water bath.