Which of the following best describes gravity

a molecular pull

a description of mass

a fundamental force

a kind of acceleration

1. When a motor is turned on, electrical energy is transformed to mechanical energy plus heat energy. True or False 2. The outward evidence for this transformation can be seen only in the mechanical motion of the motor. True or False 3.

Imagine a ringing bell set inside a sealed glass jar. Once all the air is removed and a vacuum is crated, the ringing sound is no longer heard. Explain why this happens. A. The lack of air in the jar causes the ringing to stop. B.

Suppose you want to separate the leaves, acorns, and twigs from a pile of soil. Filtration and distillation are two processes of seperating mixtures. Explain which process you would use and why.

1) A crane uses an average force of 5,200 N to lift a girder 25 m. How much work does the crane do on the girder? 2) An apple weighing 1 N falls a distance of 1 m. How much work is done on the apple by the force of gravity?

The force a magnet exerts on another magnet, on iron or a similar metal, or on moving charges is A. proportional to the mass of the magnet. B. an electric force. C. a magnetic force. D. proportional to the charge of the magnet.

One of the heating systems we talked about in this course comprises of a system of ducts. What is the process by which heat is transferred in this system? a. Conduction b. Convection c. Radiation d. None of the above

If the north pole of a magnet in a compass is attracted to Earth's geographic north, what must be the polarity of Earth's magnetic north pole? A. north B. south C. It can't be determined from the information given.

A canoe started its trip at 8 am. If the cannoe travelled at a speed of 70 mph how far did it travel by 1:36 pm?

1. Tariff of 1828 John C. Fremont 2. abolitionist who led the raid on Harper's Ferry John Brown 3. published The Liberator Santa Anna 4. Underground Railroad Harriet Tubman 5. died at the Alamo William Lloyd Garrison 6.

Which interaction of nature is weakest? a. strong c. electromagnetic b. weak d. gravitational