Question

Determine the minimal force (P) required to hold the wheel stationary. Express your answer to three significant figures and include the appropriate units.

a) P = _____ N
b) P = _____ dyn
c) P = _____ kg m/s^2
d) P = _____ lb

Answer 1

The minimal force P required to hold the wheel stationary is 409 N, which can also be expressed as 40,900,000 dynes, 409 kg m/s^2, or approximately 91.946 pounds.

Step-by-step explanation:

To determine the minimal force (P) required to hold the wheel stationary, we must first understand the forces acting on the wheel. According to the free-body diagram provided, the normal force (N) that must be countered by force P is 409 N to keep the wheel stationary. We will use the value of N to express force P in different units.

To convert N to the appropriate units:

• Newtons (N): The force is already given in newtons, so P = 409 N.
• Dynes (dyn): Since 1 N = 105 dynes, P = 409 N × 105 dynes/N = 40,900,000 dynes.
• Kilogram-meter per second squared (kg m/s2): This is equivalent to the unit of newtons, so P = 409 kg m/s2.
• Pounds (lb): Since 1 N = 0.224808943 lb, P = 409 N × 0.224808943 lb/N ≈ 91.946 lb.

Therefore, the minimal force required to hold the wheel stationary in different units is:

1. P = 409 N
2. P = 40,900,000 dyn
3. P = 409 kg m/s2
4. P = 91.946 lb