Non-Contact Forces

Which of the following forces cannot act from a distance?

• magnetism
• electricity
• kinetic friction
• gravity

When a satellite is sent into space, what causes it to orbit a planetary body?

• The satellite enters the planet's gravitational field and falls into orbit around it
• The force of thrust sends it into orbit around the planet
• The planet's magnetic pull attracts the object into the field
• Satellites do not orbit a planet they only pass near planets on their journey through space 

Each non-contact force has an area of influence surrounding it.  What is this area called?

• gravitational attraction
• influence center
• field 
• attraction 

If iron filings are sprinkled around the magnet, what will happen? 

• The filings will move away from the magnet's field.
• The filings within the magnetic field will show an attraction between the north and south poles.
• The filings will not create a pattern.
• The filings within the magnetic field will show how the 2 ends of the magnet are repulsive.

The diagram below shows that ______________________.

• As distance increases, the electric force increases.
• As distance decreases, the objects become less attractive.
• Electric forces are only slightly affected by distance.
• As distance increases, the electric force decreases.

Which answer best describes this image?

• The positive charge is repelling the negative charge.
• The blue charged object will repel the negatively red charged object.
• The positively charged red object will be attracted to the negatively charged blue object.

Which of the following statements is true?

• When an object gains electrons, its positive charge increases.
• When an object gains electrons, its negative charge increases.
• When objects gain protons, they become positively charged.
• When objects transfer neutrons, the charge increases.

If each object has the same mass, which pair has the strongest gravitational attraction?

• The first, because it appears to weigh the most.
• The first, because the arrows are thickest.
• The  second, because it has an even balance of weight and distance.
• The first, because the objects are closest together.

What does the law of universal gravitation describe?

• Objects are attracted to one another based on the distance between them and their masses.
• Objects repel each other if their mass is too small or their distance is too great.
• All objects experience gravity based on the amount of magnetism they encompass.
• An object's gravitational pull is determined solely by the amount of mass it contains.

Which of the following names the interaction of electric fields and magnetic currents?

• electromagnetism
• electric field lines
• magnetic and electric stations
• magnetism and gravity