Question 1: Define elastic potential energy in your own words.

Answer: Elastic potential energy is the stored energy in an object when it is stretched or compressed, due to its elasticity.

Question 2: Explain how a forensic scientist might use the concept of elastic potential energy when analyzing a broken rubber band at a crime scene.

Answer: A forensic scientist can analyze the deformation and energy stored in the rubber band to estimate the force and energy involved in its breakage, helping to determine if it was used as a weapon or in an altercation.

Question 3: What is the formula for elastic potential energy stored in an elastic object?

Answer: Elastic potential energy (U) = 0.5 × k × x², where k is the spring constant and x is the extension or compression from the equilibrium position.

Question 1: A forensic investigator finds a rubber cord stretched by 0.15 meters with a spring constant of 600 N/m. Calculate the elastic potential energy stored in the cord.

Answer: U = 0.5 × 600 N/m × (0.15 m)² = 6.75 Joules

Question 2: If a metal spring with a spring constant of 800 N/m is compressed by 0.05 meters, what is the elastic potential energy stored?

Answer: U = 0.5 × 800 N/m × (0.05 m)² = 1 Joule

Question 1: Describe a basic experimental setup to measure the elastic potential energy stored in a stretched rubber band in a forensic investigation.

Answer: Attach the rubber band to a fixed point, stretch it by a known distance, measure the extension, determine the spring constant through calibration, then calculate the stored energy using the formula U=0.5×k×x².

Question 2: Identify three safety precautions that should be taken when handling elastic materials in a forensic laboratory.

Answer: Wearing safety goggles to prevent injury from snapping elastic, handling materials with care to avoid overstretching, and ensuring the workspace is clear of obstacles to prevent accidents.

Question 3: Explain how the elastic energy in a stretched object could help forensic scientists estimate the force exerted during a breakage incident.

Answer: By calculating the elastic potential energy stored in the object prior to breakage, forensic scientists can use the energy and deformation data to estimate the force involved during the incident, providing insights into the severity and nature of the force applied.

Question 1: A forensic case involves a steel wire that was stretched by a force causing it to store 10 Joules of elastic energy before snapping. If the wire's spring constant is 2000 N/m, what was the extension of the wire?

Answer: x = √(2 × U / k) = √(2 × 10 J / 2000 N/m) = √(0.01) ≈ 0.1 meters

Question 2: In a forensic scenario, a piece of elastic material was found deformed and is believed to have stored 5 Joules of energy. If the material was stretched by 0.2 meters, estimate its spring constant.

Answer: k = 2 × U / x² = 2 × 5 J / (0.2 m)² = 10 / 0.04 = 250 N/m

Question 3: Discuss how forensic investigators can use the concept of elastic potential energy to determine whether a weapon, such as a slingshot, was used during a crime.

Answer: Investigators can analyze the deformation and energy stored in the slingshot's elastic components to estimate the force and energy imparted to the projectile. This helps determine if the elastic stored energy was sufficient to cause the observed damage or injury, thus linking the weapon to the incident.