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Impulse-Momentum Theorem:
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The Impulse-Momentum Theorem states that the impulse on an object equals the change in its momentum. This fundamental principle in physics connects force, time, and momentum change, demonstrating how a force acting over time affects an object's motion.
The calculator uses the impulse-momentum equation:
Where:
Explanation: The theorem shows that the same change in momentum can be achieved with a small force acting over a long time or a large force acting over a short time.
Details: Calculating impulse is crucial for understanding collisions, safety design (like airbags and crumple zones in cars), sports mechanics, and many engineering applications where forces act over time intervals.
Tips: Enter the average force in newtons (N) and the time interval in seconds (s). The time value must be positive. The calculator will compute both impulse (J) and momentum change (Δp), which are numerically equivalent.
Q1: What's the difference between impulse and momentum?
A: Momentum is a property of a moving object (p = mv), while impulse is the change in momentum caused by a force acting over time (J = F×Δt = Δp).
Q2: Why are impulse and momentum change equal?
A: This equality comes from Newton's second law (F = ma) and the definition of acceleration (a = Δv/Δt). Combining these gives F×Δt = m×Δv, which is Δp.
Q3: What are typical units for impulse and momentum?
A: Both are measured in N·s or kg·m/s. These units are equivalent since 1 N = 1 kg·m/s², so 1 N·s = 1 kg·m/s.
Q4: How does impulse relate to safety equipment?
A: Safety devices increase the time over which a force acts, reducing the peak force for a given momentum change. This principle is used in airbags, seatbelts, and padding.
Q5: Can impulse be negative?
A: Yes, impulse can be negative if the force direction opposes the positive coordinate direction, indicating a decrease in momentum.