Psci 1030 Online Lab 3: Forces And Motion

Psci 1030 Online Lab 3 Forces And Motion

The goal of this lab is to understand the relationship between net forces, acceleration, and mass. This lab also introduces you to kinetic and potential energy. You will investigate these concepts through a series of problems and a simulation. Read over the entire lab procedure below, then complete each task and record your findings in the data section at the end of the lab. Upon completion, save this document as a PDF with your name in the filename in the form "Yournamehere -forces.pdf" and upload to the assignment box on online campus.

Newton's Second Law of Motion expresses the relationship between the acceleration of an object, the mass of the object, and the net (or total) force acting on it. In equation form this is given as Fnet = ma. Fnet is the sum of the forces acting on the object. If two forces are acting in the same direction, then they add together to produce the sum. If, however, the forces are in opposite directions, then we take the difference in the forces and assign the direction of the larger force as the direction of the sum. For example, in the figure below, the net force on block A is 200 N to the right, while the net force on block B is 50 N to the left. The acceleration of block A would be: Fnet = ma 200 = 50a a = 4 m/s² to the right. Similarly, the acceleration of block B would be 2 m/s² to the left.

PROCEDURE A. Net force, acceleration, and mass calculations. Below there are a series of figures showing the forces acting on a box. You will determine the acceleration of the box (magnitude and direction), the direction and magnitude of any unknown forces acting on the box, or the mass of the box, whichever quantity is unknown. You will record your answers on the last page, Part A.

1. The 50 kg box has a 200-N force acting on it. There is a 40 N friction force acting on the box. Determine the acceleration (magnitude and direction) of the box, noting that friction always acts in the direction opposite to motion.
2. The 20 kg box shown is accelerating to the left at 5 m/s². There is a 5N friction force acting on the box. Determine the applied force (magnitude and direction).
3. The box shown accelerates to the right at 2.50 m/s². The applied force acting on the box has a value of 20 N and the friction force has a value of 2.5 N. Determine the mass of the box.
4. The 6.5 kg box shown has acceleration to the left of 3.50 m/s². There is an applied force of 50 N acting on the box. Determine the magnitude of the friction force, and the direction acting on the box.

PROCEDURE B. Projectile Motion Simulation Software Requirements: This simulation is HTML5 based. This means you can run the simulation directly through your web browser.

1. Go to the website Projectile Motion Simulation.
2. Set up the applet so that the Initial height = 0, and initial speed = 10 m/s, mass = 10 kg.
3. Start the angle of inclination at 15°.
4. Press start. Record the horizontal distance and maximum height in the data sheet.
5. Press reset and change to 25°. Repeat step 4, recording horizontal distance and maximum height.
6. Repeat by increasing 10° each trial until you reach 75°, recording each data point. Note: you will have to press “reset” after each round.
7. Change the applet to show “Energy” rather than position, you have the option in the green box.
8. Press the “slow motion” box. Watch what happens to the kinetic and potential energy as the ball moves up and then back down. Describe what you observe.

Paper For Above instruction

The assigned laboratory exercise focuses on understanding and applying fundamental concepts of forces, motion, energy, and projectile behavior through analytical problem-solving and simulation exercises. The first part emphasizes calculating net force, acceleration, and mass for various physical scenarios involving friction and applied forces, reinforcing Newton’s Second Law. The second part introduces projectile motion via an HTML5 based simulation, allowing experimentation with launch angles, initial speeds, and energy transformations to comprehend their effects on distance, height, and energy dynamics. Together, these activities aim to deepen comprehension of classical mechanics principles essential to physics education and real-world applications.

In complex physical systems, forces can be categorized broadly as contact or non-contact forces. Friction, an example of a contact force, opposes motion and significantly impacts acceleration and energy transfer. Calculations for forces require understanding net force, which sums all individual forces considering their directions. For example, for a 50 kg box subjected to a 200 N force and a 40 N friction force, the net force determines whether the box accelerates and at what rate. In this case, net force = 200 N - 40 N = 160 N, resulting in an acceleration of a = F/m = 160 N / 50 kg = 3.2 m/s² in the force direction.

Conversely, to determine the applied force on a box with known mass and acceleration, sum all known forces and solve for the unknown. For instance, if a 20 kg box accelerates to the left at 5 m/s² with a 5 N friction force, the applied force can be calculated as F_applied = m * a + F_friction = (20 kg)(5 m/s²) + 5 N = 100 N + 5 N = 105 N, directed leftward.

Similarly, when given the acceleration, applied force, and friction, the mass can be derived. For example, if a box accelerates at 2.5 m/s² with an applied force of 20 N and a friction force of 2.5 N, the mass is m = (F_applied - F_friction) / a = (20 N - 2.5 N) / 2.5 m/s² = 17.5 N / 2.5 m/s² = 7 kg.

Understanding projectile motion involves analyzing the interplay of initial velocity, launch angle, and gravitational forces. The simulation demonstrates that the maximum horizontal distance (range) does not occur at 45°, as often suggested, due to factors like air resistance and energy exchange. In the simulated data, the angle producing the greatest range varies, but theoretical models suggest 45° is optimal in ideal vacuum conditions. When energy conversion is visualized, kinetic energy peaks at mid-flight, while potential energy is highest at the peak height, emphasizing energy transformation during projectile motion.

Proper interpretation of the energy changes observed in the simulation under slow motion reveals that kinetic energy increases as the projectile accelerates upward from the ground, peaks at the highest point, then decreases during descent, while potential energy continually increases with height until the apex, then decreases. These observations reinforce the conservation of energy principles and the importance of initial conditions in trajectory planning.

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