Question

Below is a diagram showing two masses hanging by a rope over a pulley if negligible mass.
If friction is negligible, what is the magnitude of the acceleration of the masses?

• A. $3.3m/s^2$
• B. $9.8m/s^2$
• C. $4.9m/s^2$
• D. $5.0m/s^2$
• E. $2.9m/s^2$

Answer 1

Answer: (A)

$3.3m/s^2$

As pulley has negligible mass so the tension on the string for both masses will be same and the acceleration of each mass will be a (say).

From FBD: $5a=T-5g....\left(1\right)$ and $10a=10g-T...\left(2\right)$

$\left(1\right)+\left(2\right)$ , we get $15a=5g$ or $a=g/3$

or $a=10/3=3.3m/s^2$