A rock of mass `m` is dropped to the ground from a height `h`. A second rock, with mass `2m`, is dropped from the same height. When the second rock strikes the ground, what is its kinetic energy? (a) Twice that of the first rock, (b) four times that of the first rock, (c) same as that of the first rock, (d) half as much as that of the first rock, (e) impossible to determine.

Explanation

To solve the problem, we need to determine the kinetic energy of the second rock when it strikes the ground and compare it to the kinetic energy of the first rock.

### Step-by-Step Solution:

1. **Identify the Variables:**
- Let the mass of the first rock be \( m \).
- Let the mass of the second rock be \( 2m \).
- Let the height from which both rocks are dropped be \( h \).
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