AP Physics 1 Practice Quiz: 2016 FRQs

The slope of the displacement-time graph represents the object's velocity because velocity is defined as the change in displacement over time. When acceleration is constant, the slope remains constant, directly indicating velocity.

According to Newton's First Law, an object moving at constant velocity has no net force acting on it. Even if there are forces present, they are balanced, resulting in zero net force.

Newton's Second Law states that the net force acting on an object is equal to the mass of the object multiplied by its acceleration, expressed as F_net = ma. The other options do not correctly capture the relationship between force, mass, and acceleration.

As the roller coaster ascends into the loop, its kinetic energy is converted into gravitational potential energy. At the top of the loop, the potential energy is at its maximum while kinetic energy is at its minimum. This energy conversion is a demonstration of the conservation of energy in a frictionless system.

In an isolated system where no external forces are acting, the total momentum remains constant. This is a direct consequence of the law of conservation of momentum. Even though individual momenta might change in collisions, the sum remains conserved.

In projectile motion without air resistance, the horizontal component of velocity remains constant due to the absence of horizontal forces. Gravity only affects the vertical motion, changing the vertical velocity over time. Therefore, the horizontal component stays unchanged throughout the flight.

The friction force for an object sliding on a surface is given by f = μN, where μ is the coefficient of friction and N is the normal force. On a horizontal surface, the normal force is equal to the weight of the object (mg). The other options do not correctly represent the friction force.

In a perfectly inelastic collision, the colliding objects stick together after impact. Momentum is conserved in such collisions while kinetic energy is not, as some of it is transformed into other forms of energy such as heat or deformation. This distinction underscores the conservation law for momentum separate from energy considerations.

Torque is the product of the force and the lever arm, which is defined as the perpendicular distance from the axis of rotation to the force's line of action. This definition is key for correctly analyzing rotational dynamics. The other options do not provide the necessary measure for torque.

Centripetal force is required to keep an object moving in a circular path and is given by the formula F = mv²/r. This force is always directed toward the center of the circle. The other provided expressions do not correctly capture this relationship.

In a frictionless pendulum, energy is continuously exchanged between potential and kinetic forms. At the lowest point of the swing, the potential energy is at its minimum while the kinetic energy is at its maximum. This change is dictated by the conservation of mechanical energy.

The period of oscillation for a mass-spring system is given by T = 2π√(m/k), derived from the basic principles of simple harmonic motion. This formula shows that the period increases with mass and decreases with a stiffer spring. The other expressions do not correctly reflect the relationship between mass, spring constant, and period.

Impulse is defined as the product of the force applied and the duration of its application, which equals the change in momentum. This is known as the impulse-momentum theorem. The other options correspond to different physical quantities.

The area under an acceleration-time graph represents the change in velocity, as acceleration is the rate at which velocity changes. By calculating the area, one integrates acceleration over time, arriving at the net change in velocity. This is distinct from displacement, which is obtained from a velocity-time graph.

In a frictionless, isolated system, the total mechanical energy (the sum of kinetic and potential energy) remains constant. As the object falls, potential energy is converted into kinetic energy while their sum does not change. This conservation of energy is fundamental in analyzing such systems.

The maximum height of a projectile is reached when its vertical velocity is zero. Using the kinematic equation for vertical motion, the maximum height is given by h_max = (v0² sin²θ)/(2g). The alternatives either use the incorrect trigonometric function or do not yield the correct dimensions.

When a wheel rolls without slipping, both its translational and rotational motions affect its acceleration. The proper relationship accounts for the moment of inertia and is given by a = (g sinθ) / (1 + I/(mr²)). This expression correctly reduces the acceleration compared to a frictionless slide due to rotational inertia.

In completely inelastic collisions, the objects merge and momentum is conserved. However, some kinetic energy is transformed into other forms such as heat or deformation energy, so mechanical energy is not conserved. This demonstrates the nuanced difference between momentum and energy conservation laws.

In an ideal simple harmonic oscillator with no damping, the sum of kinetic and potential energy - the total mechanical energy - remains constant over time. Although the individual energies vary during the oscillation, their sum does not change. This is a classic example of energy conservation in oscillatory systems.

Air resistance opposes the motion of a projectile, causing it to lose kinetic energy throughout its flight. This loss leads to reductions in both the maximum height reached and the overall horizontal range when compared to the ideal situation with no air resistance. As a result, the flight trajectory is shorter in both vertical and horizontal dimensions.