Exam 2 study questions

A 30 kg girl is riding an elevator that is accelerating downward at 2.0 m/s2.

What is her apparent weight?

• 60 N

• 234 N

• 294 N

• 354 N

Which of the four fundamental forces is responsible for binding protons together

in an atomic nucleus?

• Gravitation

• Electromagnetism

• The strong nuclear force

• The weak nuclear force

Which of the following statements does not obey Newton’s first law of motion?

• Groceries in the back of your car begin to slide to one side as you drive

  through a turn.

• Groceries in the back of your car begin to slide to the back while you drive

  with constant speed on a straight road.

• A rock will not spontaneously leap into the air.

• A space probe will travel with constant velocity for centuries without firing

  its engines.

Which of the following would decrease the drag force acting on an object?

• Increase the object’s density.

• Increase the object’s cross-section.

• Decrease the object’s speed.

• Decrease the object’s mass.

A hand pushes down on a book with mass m, as shown in the picture. Is the

normal force of the table on the book greater than, less than, or equal to mg?

• Equal to

• Less than

• Greater than

• I'd need to know the mass of the book

Scallops eject water from their shells to provide a

thrust force. The graph to the right shows data for

the initial motion of a 20-gram scallop speeding up

to escape a predator. What is the magnitude of the

net force acting on the scallop?

• 20 N

• 4.0 N

• 1.0 N

• 0.02 N