Question 1: Define the inverse square law and explain its significance in the context of light intensity during photosynthesis.

Answer: The inverse square law states that the intensity of light or other radiation decreases proportionally to the square of the distance from the source. In photosynthesis, this law explains how light intensity diminishes as the distance from the light source increases, affecting the rate of photosynthesis.

Question 2: Describe how the inverse square law affects the amount of light energy reaching a plant at different distances from a light source.

Answer: As the distance from the light source increases, the amount of light energy reaching the plant decreases proportionally to the square of the distance, meaning the light intensity drops rapidly at greater distances.

Question 1: A light source emits an intensity of 1000 lux at a distance of 1 meter. What is the light intensity at a distance of 3 meters? (Use the inverse square law formula: I₂ = I₁ × (d₁/d₂)²)

Answer: I₂ = 1000 × (1/3)² = 1000 × 1/9 ≈ 111.11 lux

Question 2: If the light intensity at 2 meters is 250 lux, what is the initial intensity of the light source at 1 meter? (Rearrange the formula: I₁ = I₂ × (d₂/d₁)²)

Answer: I₁ = 250 × (2/1)² = 250 × 4 = 1000 lux

Question 1: Describe a simple experiment to demonstrate the inverse square law using a light source and a light sensor. Identify the independent and dependent variables.

Answer: An experiment can involve placing a light source at a fixed point and measuring light intensity at various distances (e.g., 1m, 2m, 3m). The independent variable is the distance from the light source, and the dependent variable is the light intensity measured by the sensor. Safety precautions include avoiding direct eye exposure to bright light and maintaining consistent environmental conditions.

Question 2: List three safety precautions that should be followed when conducting a practical experiment involving bright light sources.

Answer: Avoid direct eye exposure to bright light, ensure the light source is stable and not overheating, and conduct the experiment in a controlled environment to prevent accidents.

Question 1: A plant is placed 2 meters away from a grow light emitting 800 lux at 1 meter. What is the expected light intensity at the plant's location? Explain your reasoning.

Answer: Using the inverse square law: I₂ = 800 × (1/2)² = 800 × 1/4 = 200 lux. Therefore, the light intensity at 2 meters is expected to be 200 lux, as light intensity decreases proportionally to the square of the distance.

Question 1: Explain how the inverse square law is important in designing artificial lighting for indoor plant growth. Include considerations for energy efficiency.

Answer: Understanding the inverse square law allows designers to position grow lights at optimal distances to ensure adequate light intensity while minimizing energy consumption. Properly applying this law ensures plants receive enough light for photosynthesis without unnecessary energy use, thereby improving efficiency and plant health.

Question 2: In sunlight, how does the inverse square law influence the amount of solar energy received on Earth's surface at different latitudes?

Answer: The inverse square law indicates that as the angle of sunlight decreases at higher latitudes, the energy received per unit area decreases, leading to less solar energy reaching Earth's surface in those regions compared to the equator where sunlight strikes more directly.