B. State whether the following statements are true or false. 1. A freely suspended bar magnet points in east-west direction.
2. Electromagnets used to remove nickel from a scrap of copper, zinc and nickel.
3. Magnets are stored in pairs such that same poles face each other.
4. When a bar magnet is broken into number of pieces each piece is complete magnet.
5. Opposite poles of two different magnets repel each other.

In a closed system, the total energy prior to an energy transformation is the total energy after. a. equal to b. unrelated to c. greater than d. less than

Laboratory experiments, observational field studies, and model-building are all examples of different forms of scientific investigations.  in what way do laboratory experiments primarily differ from other forms of scientific investigations?   a.  a laboratory experiment is the only accepted form of investigation within the scientific community.  b.  studies about how things behave in nature or studies involving very large objects are best answered through laboratory experiments.  c.  laboratory experiments involve the identification and control of variables.  d.  data can only be generated through laboratory experiments, not other forms of investigation.

Assume you measured the mass of the cart to be (500 ± 1) g and the mass of the additional mass you put on the cart to be (500 ± 1) g as well. since the scale you are using in the lab cannot measure objects heavier than 600g you will have to sum up individual pieces and propagate the error. so what would be the mass and the standard error of the cart and the mass