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**1. Homework Statement**

Hi there. I have previously asked questions on here and found it very helpful so would be grateful if someone could maybe help me again? I am currently studying for my Physics P2 GCSE unit and came across this question on the topic of Terminal Velocity.

"Two identical crates are dropped from an aircraft. One is empty and the other is full. Which will reach the ground first?"

**2. Homework Equations**

Force = Mass x Acceleration

**3. The Attempt at a Solution**

Here is the answer I have written up. I would just like some clarification as to whether I am right, along the right lines, or completely wrong please.

The heavier crate will reach the ground first. This is because there is more air resistance acting on the empty crate than the full one. After being dropped, both crates will accelerate, but because the heavier crate has more mass the downwards force on it (weight) will be greater than that on the lighter crate (f=m x a) even though both objects will accelerate by the same amount due to the pull of gravity. This means that it will take a shorter time for air resistance to balance with the weight of the lighter crate than the heavier crate, stopping it from accelerating before the heavier. This gives it a slower terminal velocity, therefore meaning that the heavier crate, with a greater terminal velocity, will reach the ground first.

I would be really grateful for some clarification on this, as I have been teaching myself practically the whole of the syllabus due to having a less than reliable teacher, so have no other way of knowing if what I have learnt is correct.

Many thanks,

Molly.