Science 6: Levitating Forces Post-test

The strength of an electromagnet can be increased by increasing the current through the wire and by __________the number of wire turns around the core.  A stronger electromagnet will also be produced if thick wire is wrapped around a core consisting of  _________ . In general increasing the size of the electromagnet increases its strength.

• increasing, metal

• decreasing, increasing

• metal, non-metal

• non-metal, metal

When an electric current flows through the wire in an electromagnet,  _______.

• the wire begins to spin

• the wire becomes very cold.

• a magnetic field is created around the wire.

• a gravitational field is created around the wire.

Why does it take more force to move a heavy box up a ramp than to move the same box down the ramp?

• There is more friction on the bottom of the box when going up a ramp.

• Gravity is pushing the box up the ramp at the same time you are pushing the box up the ramp.

• When you push an object up a ramp, you are working against gravity, which pulls the box downward.

• When you push an object up a ramp, you are working against atmospheric pressure, which is pushing downward.

The force that keeps satellites in orbit around earth is____________.

• friction

• gravity

• electrical

• magnetic

A waterfall is an example of __________.

• energy being created

• energy being destroyed

• kinetic energy being converted into potential energy

• potential energy being converted into kinetic energy

A baseball is picked up from the floor and placed on the edge of a table top.  What type of energy does the baseball have now ?

• chemical kinetic energy

• chemical potential energy

• gravitational kinetic energy

• gravitational potential energy

When you climb to the top of a water slide you are gaining_______.

• gravitational kinetic energy.

• gravitational potential energy.

• chemical kinetic energy.

• chemical potential energy.

Which of the following is an example of potential energy?

• a battery

• a moving car

• a turning propeller

• a glowing light bulb

Two airplanes are flying in the sky in such a way that the gravitational attraction between them decreases.  The planes must be flying__________.

• towards each other

• away from each other

• faster than the speed of sound

• next to each other at the same speed

Which of these terms refers to energy waiting to be released?

• total

• kinetic

• potential

• gravitational