Question 1

What does Newton's second law tell us about the relationship between force and mass?

Accepted Answer

Newton's second law, expressed as F=ma, shows that greater force is required to move objects with larger mass. For a given force, acceleration is inversely proportional to mass—smaller masses accelerate more than larger masses when the same force is applied. This fundamental relationship applies across physics and engineering.

Question 2

How does the photogate timer measure acceleration in this experiment?

Accepted Answer

The photogate timer records the time it takes for a flag on the glider to pass through it at a known distance. By dividing the flag length by this time, you calculate the glider's final velocity. Using this velocity and the distance traveled, you can then calculate acceleration using kinematics formulas.

Question 3

Why does the air track reduce friction in this Newton's second law experiment?

Accepted Answer

The air track creates a cushion of air beneath the glider, reducing friction to negligible levels. This allows the glider to move freely with minimal resistance, ensuring that the only significant force acting on it is the tension from the hanging weight, making the experimental results more accurate.

Question 4

What happens to acceleration when you increase the hanging mass while keeping the glider mass constant?

Accepted Answer

Increasing the hanging mass increases the force pulling the glider, causing acceleration to increase. As shown in the experiment, when hanging mass doubled from 10 grams to 20 grams, theoretical acceleration increased proportionally due to the greater force applied to the system.

Question 5

How do experimental and theoretical accelerations differ in this lab, and why?

Accepted Answer

Experimental acceleration is calculated from measured velocity and distance data, while theoretical acceleration is derived from Newton's second law using known masses. Differences arise from measurement accuracy limitations, small but non-negligible friction on the air track, and variations in the air pocket beneath the glider affecting tension force.

Question 6

What real-world applications use Newton's second law to calculate impact forces?

Accepted Answer

Sports medicine researchers use accelerometers in hockey helmets to measure head acceleration during impact. By applying Newton's second law with the measured acceleration and head mass, they calculate impact forces on the brain. Civil engineers similarly use sensors on footbridges to measure vertical acceleration from pedestrian loads.

Question 7

Why is the tension force in the string important for calculating theoretical acceleration?

Accepted Answer

The tension force connects the falling weight to the glider, transmitting the applied force. To derive theoretical acceleration, you must account for tension acting on both the glider and the weight. The tension equals the weight's mass times the glider's acceleration, making it essential for accurate theoretical predictions.

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