Three forces,10.0 N,20.0 N,and 15.0 N,are acting on a 9.23-kg object.Which of the following forces could also be acting on the object if it is moving with constant velocity?
A) 1.0 N
B) 19.0 N
C) 34.0 N
D) 2.0 N
E) any of the above

Question

Three forces,10.0 N,20.0 N,and 15.0 N,are acting on a 9.23-kg object.Which of the following forces could also be acting on the object if it is moving with constant velocity?
A) 1.0 N
B) 19.0 N
C) 34.0 N
D) ​2.0 N
E) ​any of the above

Quizplus · Accepted Answer

If an object is moving with constant velocity, it means that the net force acting on it is zero. Therefore, any additional force that is equal in magnitude and opposite in direction to the sum of the three given forces will also leave the net force on the object zero.

To find the sum of the given forces:

10.0 N + 20.0 N + 15.0 N = 45.0 N

Therefore, any force that is -45.0 N (in the opposite direction) can also be acting on the object without changing its constant velocity.

Looking at the choices:

A) 1.0 N - too small to counteract the sum of the given forces 
B) 19.0 N - not equal in magnitude to the sum of the given forces 
C) 34.0 N - not equal in magnitude to the sum of the given forces 
D) 2.0 N - too small to counteract the sum of the given forces

Therefore, the only option is E: any of the above, as long as the force is equal in magnitude and opposite in direction to the sum of the given forces.

Three Forces,10