# Homework Help: True of False (Net force)

1. Oct 7, 2012

### JLPG

1. The problem statement, all variables and given/known data
Indicate whether the following statements are always true or can be false. (Select T-True, F-False. If the first is F and the rest T, enter FTTTTT).

A) The net force which acts on an object which maintains a constant velocity is zero.
B) If a net force acts on an object, the object's velocity will change.
C) In order not to slow down, a truck moving at a constant velocity needs a small net force applied.(ignore friction)
D) If an object's speed does not change, no net force is acting on the object.
E) During the collision of a large truck with a car, the car exerts an equal size force on the truck as the truck exerts on the car.
F) If two object have the same acceleration, they are under the influence of equal forces.

2. Relevant equations

F=ma

3. The attempt at a solution
A) True--> if constant velocity= 0 acceleration and F=m(0)= 0
B) ?
C)False--> acceleration can be zero and still keep a constant velocity
D)True? why
E)True--> equal and opposite forces
F)True? why

2. Oct 7, 2012

### SammyS

Staff Emeritus
What do you want from us?

Some of your answers are correct. Others are not.

Can velocity change without speed changing?

3. Oct 7, 2012

### PhanthomJay

Of the 5 you attempted, you have three correct. Hint: Apply Newton 2.

4. Oct 8, 2012

### JLPG

Thank-you, I figured it out.
T
T
F
F
T
F
:)