Question

A certain force gives an acceleration
of 4 m/s 2 to a 20-kg block. What
acceleration will be imparted by the same
force to a 15-kg block?

Answer 1

Let's first find the magnitude of the force that accelerates a 20-kg block at $4\ \dfrac{m}{s^2}$:

$$F=ma=20\ kg\cdot 4\ \dfrac{m}{s^2}=80\ N.$$

Finally, we can find the acceleration imparted by the same force to a 15-kg block:

$$a=\dfrac{F}{m}=\dfrac{80\ N}{15\ kg}=5.33\ \dfrac{m}{s^2}.$$

Answer:

$a=5.33\ \dfrac{m}{s^2}.$