Forces- Review

Forces- Review

Multiple Choice

To have a net force applied we need to have what?

• acceleration

• velocity

• time

• distance

Multiple Choice

If we are moving forward at a constant velocity what are we in?

• static equilibrium

• dynamic equilibrium

• not in equilibrium

• acceleration

Multiple Select

If you are standing still what forces are acting on you?

• normal

• weight

• friction

• drag

Open Ended

Is a force a vector? why or why not?

Multiple Select

choose the non contact forces

• gravity

• friction

• electricity

• magnetism

Multiple Choice

Forces need an agent(doer) and act on an object.

• Yes

• No

Multiple Choice

In equilibrium the net force is not 0?

• True

• False

Multiple Select

Choose the opposition forces

• static friction

• kinetic friction

• thrust

• drag

Open Ended

Could we move forward if we did not have static friction. Why or why not?

Multiple Choice

What law tells us about aaction/reaction pairs?

• 1st

• 2nd

• 3rd

Open Ended

In crash tests with cars, we see that test dummies do not stop when the car does, what law tells us why this happens? Explain.

Multiple Choice

The magnitude of tension force will be equal to the

• stationary object

• pulling object

• 1/2 the pulling object

Multiple Choice

A box is connected to another box and the rope is around a massless frictionless pulley. It is in equilibrium. Tension in the rope is

• T= mg

• T< mg

• T> mg

Open Ended

Why is a terminal speed able to be reached?

Multiple Choice

Reynold's number is

• inertial forces/viscous forces

• viscous forces/ inertial forces

• air resistance

Multiple Choice

What is the coefficient of f_s if the max potential is 440 N and normal force is 900 N?

• .6

• .49

• 2.0

Multiple Choice

A man has a mass of 80 kg. In the elevator he accelerates from rest to 3.3 m/s. His apparent weight is 650 N. Was he going up or down? How long did it take to reach his final velocity?

• Down, 2 sec

• Up, 2 sec

Open Ended

An object has weight, but it is weightless. How can this be?( think about what apparent weight is)