All of those! A qualitative observation is any one that doesn't include numbers. <em>Quantitative </em>observations include numbers, but not usually any other kind of information.
So the force that the gymnast with a mass m=45 kg, has to exert against the ground to stop if her acceleration is a=8*g, where g=9.81 m/s², can be obtained from the Newtons second law: F=m*a, where F is the force, m is the mass and a is acceleration.
F=m*a=m*8*g=45*8*9.81=3531.6 N.
So the force that a gymnast has to exert on the mat in order to stop is F=3531.6 N.
Answer: an isolated system
Explanation:
Answer:
Explanation:
A solid comes into your hands with a definite shape. Think of something like a rock. It is not going to be easy to change its shape. So the answer is a solid.
Answer:
False
Explanation:
Water hardness in most groundwater is due to a natural occurrence caused by the weathering of limestone, sedimentary rock and calcium bearing minerals. Hardness can also occur locally in groundwater from chemical and mining industry effluent or excessive application of lime to the soil in agricultural areas.
Limestone is not a metallic element or metallic alloy, although it does contain the metallic element calcium, it is not formed by the same processes as metals are.
