Force and Laws of Motion

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The fielder increases the time during which the ball's velocity decreases to zero. According to Newton's second law (F = ma), when time increases, acceleration decreases, which reduces the force on hi…

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Inertia is the natural tendency of an object to resist change in its state of motion or rest. Mass is the measure of inertia - heavier objects have more inertia. For example, it's easier to push an em…

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Given: m = 1000 kg, u = 30 m/s, v = 0 m/s, t = 4 s Using F = m(v-u)/t F = 1000 × (0-30)/4 = 1000 × (-30)/4 = -7500 N The negative sign indicates the force opposes motion. The magnitude of braking forc…

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When the bus starts suddenly, our feet move with the bus due to friction, but our upper body tends to remain at rest due to inertia (Newton's First Law). This creates a relative backward motion of our…

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The card moves away quickly, but the coin falls straight down into the glass due to inertia. The coin tends to remain at rest (Newton's First Law) even when the card is removed suddenly. This happens …

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Momentum is the product of an object's mass and velocity: p = mv. It has both magnitude and direction (same as velocity). The SI unit of momentum is kg⋅m/s (kilogram meter per second). Momentum repres…

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When a gun is fired, it exerts a forward force on the bullet (action). The bullet exerts an equal and opposite force on the gun (reaction). Since the gun has much greater mass than the bullet, its acc…

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Balanced forces: Equal forces acting in opposite directions that cancel each other out, causing no change in motion. Example: A book on a table (weight balanced by normal force). Unbalanced forces: Ne…