Let's solve this step by step, starting with the information provided:

Given Data:

• Mass (m) of the object = 6 kg
• Acceleration (a) = 0 m/s² (indicating constant velocity)
• Frictional force (F_fric) = 15 N
• Applied force (F_app) (unknown but to be calculated)
• Gravitational force (F_grav) (unknown but to be calculated)
• Normal force (F_norm) (unknown but to be calculated)

Since the object is moving at a constant velocity, we know that the net force $F_{\text{net}}$ in both the horizontal and vertical directions is zero, as there is no acceleration.

Step 1: Determine Gravitational Force ($F_{\text{grav}}$)

The gravitational force is calculated using the formula: $F_{\text{grav}} = m \times g$ where $g$ is the acceleration due to gravity, typically $9.8 \, \text{m/s}^2$.

So, $F_{\text{grav}} = 6 \, \text{kg} \times 9.8 \, \text{m/s}^2 = 58.8 \, \text{N}$

Step 2: Determine the Normal Force ($F_{\text{norm}}$)

Since there is no vertical movement, the normal force must balance out the gravitational force. Thus, $F_{\text{norm}} = F_{\text{grav}} = 58.8 \, \text{N}$

Step 3: Determine the Applied Force ($F_{\text{app}}$)

In the horizontal direction, since the object is moving at a constant velocity, the applied force $F_{\text{app}}$ must balance out the frictional force $F_{\text{fric}}$.

$F_{\text{app}} = F_{\text{fric}} = 15 \, \text{N}$

Step 4: Calculate the Net Force ($F_{\text{net}}$)

Since there is no acceleration, the net force in both the horizontal and vertical directions must be zero: $F_{\text{net, x}} = F_{\text{app}} - F_{\text{fric}} = 0$ $F_{\text{net, y}} = F_{\text{norm}} - F_{\text{grav}} = 0$

Summary of Results:

• $F_{\text{grav}} = 58.8 \, \text{N}$
• $F_{\text{norm}} = 58.8 \, \text{N}$
• $F_{\text{app}} = 15 \, \text{N}$
• $F_{\text{net}} = 0$

Would you like any further details on these calculations?

Here are some related questions to consider:

1. What would happen to the net force if the object started accelerating?
2. How would the forces change if the mass of the object increased?
3. What is the role of friction in maintaining a constant velocity here?
4. How would the applied force need to change if the frictional force were reduced?
5. How does the normal force relate to gravitational force in this scenario?

Tip: When dealing with forces in constant velocity scenarios, always remember that net force is zero, as acceleration is zero.