Question

1. a light - dependent resistor (ldr) is a type of resistor, and its resistance is dependent on the amount of light shining on it.

the diagram below shows what an ldr looks like and the circuit symbol of an ldr.
tanisha conducts an experiment to investigate how an ldr affects the brightness of a bulb. she sets up a circuit as shown below. she places the ldr in a black box that has an opening.
the table below shows how the resistance of the ldr changes with the amount of light shining on it.

amount of light shining on ldr	resistance of ldr / ω
dim light	50
bright light	20
very bright light

(a) complete the table above. 1

Explanation:

Step1: Analyze the trend

From the table, as the light becomes brighter (from no light to dim to bright), the resistance of the LDR decreases (100 → 50 → 20). So for very bright light, the resistance should be less than 20. A reasonable value following the decreasing trend (e.g., as light intensity increases, resistance decreases further) would be a value like 10 (or another value less than 20, but the common trend here is a decreasing resistance with increasing light, so we can infer the pattern: no light (100), dim (50, half of 100), bright (20, which is 100*(20/100)=20, and the pattern of decreasing by a factor or a consistent drop; another way: from no to dim: 100 - 50 = 50 drop; dim to bright: 50 - 20 = 30 drop; but maybe the trend is more about inverse relation to light intensity, so very bright light would have lower resistance, say 10 (or any value less than 20, but typically in such problems, the resistance continues to decrease. Let's check the pattern: 100 (no), 50 (dim, 100/2), 20 (bright, 100/5), so maybe very bright could be 100/10 = 10, or another logical step. But the key is the trend: more light → lower resistance. So we need to put a value less than 20. A common answer here would be 10 (or 5, but 10 is a typical continuation).

Step2: Fill the table

Based on the trend (increasing light intensity leads to decreasing resistance), for "very bright light", the resistance should be less than 20. A typical value following the decreasing pattern (100, 50, 20, ...) could be 10 (or other values like 5, but 10 is a reasonable step). So we fill the table with a value less than 20, e.g., 10.

Answer:

For the "very bright light" row, the resistance of the LDR should be a value less than 20 (e.g., 10 Ω, or other values like 5 Ω, but a common answer is 10 Ω following the decreasing trend). So the completed table cell for "very bright light" and "Resistance of LDR / Ω" would be \boxed{10} (or other appropriate value less than 20, but 10 is a typical answer here).