According to Newton's second law of motion, the acceleration (a) of an object is given by the equation:
\[ a = \frac{F}{m} \]
where \( F \) is the net force applied to the object, and \( m \) is the mass of the object.
In this case, if Trevor applies the same amount of force \( F \) to both boxes:
-
For Box A (mass = 4 kg): \[ a_A = \frac{F}{4} \]
-
For Box B (mass = 8 kg): \[ a_B = \frac{F}{8} \]
Now, comparing the accelerations:
- Box A's acceleration \( a_A = \frac{F}{4} \)
- Box B's acceleration \( a_B = \frac{F}{8} \)
Since \( \frac{F}{4} \) is twice \( \frac{F}{8} \), we can see that:
\[ a_A = 2 \cdot a_B \]
This means that box A will accelerate at twice the rate of box B.
Thus, the correct answer is:
B. box A will accelerate at twice the rate of box B.