Question

For a moving object, the force acting on the object varies directly with the object's acceleration. When a force of 72 N acts on a certain object, the acceleration of the object is 9 m/s^2. If the acceleration of the object becomes 5 m/s^2, what is the force?

a) 40 N
b) 45 N
c) 50 N
d) 55 N

Answer 1

The force acting on a moving object is directly proportional to its acceleration. After calculating the object's mass, the new force with changed acceleration is determined to be 40 N, which corresponds to answer a).

Step-by-step explanation:

For a moving object, the force acting on the object varies directly with the object's acceleration. In other words, force is the product of mass and acceleration (F = ma). When a force of 72 N acts on a certain object, causing it to accelerate at 9 m/s², this relationship can be used to find the mass of the object. To find the new force when the acceleration is 5 m/s², we first calculate the mass using the initial conditions:

m = F / a = 72 N / 9 m/s² = 8 kg

Then, using the mass, we calculate the new force with the new acceleration:

F = m × a = 8 kg × 5 m/s²

Therefore, the new force is:

F = 40 N

So, the correct answer is a) 40 N.