Answer:
m = 5 [kg]
Explanation:
To solve this problem we must use Newton's second law, which tells us that the sum of forces in a body must be equal to the product of mass by acceleration.
ΣF = m*a
Where:
F = force [N]
m = mass [kg]
a = acceleration = 4 [m/s^2]
Now replacing:
50 - 30 = m*(4)
m = 5 [kg]
