Question

A nail is hit with a hammer with a force of 10 Newtons. The nail moves into the wood with a force _____.

Answer 1

Which of the following statements is true?



The more mass an object has the more inertia it has.

The more mass an object has the slower it will accelerate.

The more mass an object has the more force needed to move it.

All of the above.

Answer 2

If a machine decreases the distance an object moves, it must also _____.



decrease the object's mass

increase the object's acceleration

increase the force used to move the object

decrease the force used to move the object

Answer 3

According to Newton's Second Law of Motion, an increase in force will _____.



increase acceleration

decrease acceleration

increase mass

have no effect on acceleration

Answer 4

According to Newton's First Law of Motion _____.



objects in motion stop moving once force is removed

objects at rest can start moving on their own

objects in motion will keep moving unless acted upon by force

every action has an equal and opposite reaction

Answer 5

Choose all the answers that apply.

Power is calculated using ___.

timeworkfrictionhorsepowerefficiency

Answer 6

Friction _____.



is always and unwanted force

works in the opposite direction of motion

causes machines to work 100 percent efficiently

can be increased using lubricants, like oil

Answer 7

A ball rolling across the floor keeps moving until it is stopped by friction. This example demonstrates _____.



Newton's First Law of Motion

Newton's Second Law of Motion

Newton's Third Law of Motion

the work principle

Answer 8

How much work can be done per second by a one horsepower engine?



275 ft-lbs./sec

550 ft-lbs./sec

1,100 ft-lbs./sec

1,650 ft-lbs./sec

Answer 9

Rebecca jogs in place for two minutes before her track meet. Rebecca weighs 100 pounds. Which of the following statements is true?



Rebecca has done 200 foot-pounds of work.

Rebecca has not done work because she has not moved a distance.

Rebecca would accelerate more quickly is she weighed 120 pounds.

Rebecca has done 100 foot-pounds of work.

Answer 10

Felipe weighs 50 pounds. He runs up a 4 foot flight of stairs in 10 seconds. What is Felipe's power output?



4 ft-lbs./sec

10 ft-lbs./sec

20 ft-lbs./sec

50 ft-lbs./sec

Answer 11

Choose all the answers that apply.

Force has _____.

magnitudedirectiontimeefficiency