Is the Net Force Zero in Constant Velocity and Other Physics Queries?

[JLPG]

Homework Statement

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.

Homework Equations

F=ma

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

 

[SammyS]

Homework Statement

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.

Homework Equations

F=ma

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

What do you want from us?

Some of your answers are correct. Others are not.

Can velocity change without speed changing?

 

[PhanthomJay]

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

 

[JLPG]

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

 

[rdl]

B) True--> Newton's Second Law states that F=ma, so if a force is applied to an object, it will experience an acceleration.
D) True--> If an object's speed is not changing, it means that the acceleration is 0, and according to Newton's Second Law, F=ma, so if a=0, then F=0.
F) True--> According to Newton's Second Law, if two objects have the same acceleration, they must have the same net force acting on them.