Homework Help

Is it correct to say that no force acts on a body at rest?Multiple Choice A.) No force...

user profile pic

lala2pretty | Student, Undergraduate | (Level 1) Honors

Posted October 14, 2009 at 9:30 PM via web

dislike 1 like

Is it correct to say that no force acts on a body at rest?

Multiple Choice

A.) No force acts on a body at rest; if at least one force acted on it the body would move.

B.) No net force acts on a body at rest; when the net force is zero, the body is in static equilibrium

C.) No force acts on a body at rest; all forces cancel each other

D.) No net force acts on a body at rest; no force acts on the body at all

E.) All are wrong.

4 Answers | Add Yours

user profile pic

pohnpei397 | College Teacher | (Level 3) Distinguished Educator

Posted October 14, 2009 at 10:34 PM (Answer #1)

dislike 1 like

The correct answer here is B.  To understand why, think about anything that's stationary right now, for example the screen on your computer.  You know that it cannot be true that no force is acting on it.  After all, every object on Earth is being acted on by gravity at every moment.

So how come some objects don't move if gravity is acting on them?  It's because there are other forces that cancel out the force of gravity.  In this case, it's something called the "normal force" which is the term for the force that opposes gravity.

user profile pic

tandrewfield | Middle School Teacher | (Level 1) Adjunct Educator

Posted October 14, 2009 at 10:33 PM (Answer #2)

dislike 0 like

There are forces acting on a body at rest in all situations except theoretical ones.  For example, a motionless bowling ball sitting on the floor has a gravitational force acting upon it.  In fact, that is what keeps it motionless. 

The bowling ball also exerts a gravitational pull on the earth.  The net force acting upon the ball is zero, which puts the ball in static equilibrium, or more accurately, mechnical equilibrium.

user profile pic

seanmcfaul23 | Student, Grade 10 | eNotes Newbie

Posted June 28, 2010 at 3:13 PM (Answer #4)

dislike 0 like


user profile pic

parama9000 | Student, Grade 11 | (Level 1) Valedictorian

Posted February 28, 2014 at 3:06 PM (Answer #5)

dislike 0 like

It would be B.

Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes