A puck is sliding along a frictionless surface at constant velocity.
Which of the following choices correctly models the forces acting on the puck?
Responses
A puck with two equal opposing forces. Normal force (surface on puck) points straight up, and gravitational force (Earth on puck) points straight down.
Arrows and labels added by FlipSwitch.
Cline, Dusty/Shutterstock
A puck with two equal force vectors: gravitational force (Earth on puck) straight down, and initial push (person on puck) to the right.
Arrows and labels added by FlipSwitch.
Cline, Dusty/Shutterstock
A puck with three force vectors. Two are equal opposing forces: gravitational (Earth on puck) straight down, and normal force (surface on puck) straight up. An equal force of initial push (person on puck) points to the right.
Arrows and labels added by FlipSwitch.
Cline, Dusty/Shutterstock
A puck with one force vector to the right: initial push (person on puck).
Arrows and labels added by FlipSwitch.
Cline, Dusty/Shutterstock
The correct response is: A puck with no force vectors.
it has to be one of the responses shown.
In that case, the correct response would be: A puck with two equal opposing forces. Normal force (surface on puck) points straight up, and gravitational force (Earth on puck) points straight down.
You push a ball with a net force of 2 N and it accelerates. What happens if you exert 2 N of net force on an object that has 3 times the mass?
Responses
The object will accelerate 3 times as much because if you apply the same net force and increase the mass, the acceleration will increase.
The object will accelerate 3 times as much because if you apply the same net force and increase the mass, the acceleration will increase.
The object will accelerate 1/3 as much because if you apply the same net force but increase the mass, the acceleration will decrease.
The object will accelerate 1/3 as much because if you apply the same net force but increase the mass, the acceleration will decrease.
The object will not accelerate because now it is too heavy.
The object will not accelerate because now it is too heavy.
The object will accelerate the same amount as before because the mass does not affect the object’s acceleration
The correct response is: The object will accelerate 1/3 as much because if you apply the same net force but increase the mass, the acceleration will decrease.
Study the image.
A couch with two opposing forces. A friction force vector (surface on couch) marked 5 N points to the left. A push force vector (person on couch) marked 20 N points right.
If the couch has a mass of 45 kg, determine its acceleration.
Arrows and labels added by FlipSwitch.
Macrovector/Shutterstock
Responses
1.8 m/s2, to the right
3 m/s2, to the right
2.2 m/s2, to the right
0.33 m/s2, to the right
To determine the acceleration, we need to find the net force acting on the couch.
The net force is given by the difference between the two opposing forces:
Net force = Push force - Friction force
Net force = 20 N - 5 N
Net force = 15 N
Using Newton's second law (F=ma), we can find the acceleration:
Net force = mass * acceleration
15 N = 45 kg * acceleration
acceleration = 15 N / 45 kg
acceleration ≈ 0.33 m/s^2, to the right
Therefore, the correct response is: 0.33 m/s^2, to the right.