Question

For a moving object, the force acting on the object varies directly with the object's acceleration. When a force of 28 N acts on a certain object, the acceleration of the object is 7 /ms2. If the force is changed to 8 N, what will be the acceleration of the object?

Answer 1

Answer:
`2 m/s^(2)`

Explanation:

According to Newton's second law, the acceleration
`a` of an object with mass
`m` is directly proporional to the force
`F` applied to that object:

`F=m.a` (1)

In the first case we are given the following data:

`F=28 N`

`a=7 m/s^(2)`

Substituting this information in (1):

`28 N=(m)(7 m/s^(2))` (2)

Isolating
`m`:

`m=4 kg` (3) This is the mass of the object

Now if we keep this calculated mass, but we change the applied force to
`F=8 N`, we will have:

`8 N=(4 kg)a` (4)

Isolating the acceleration:

`a=2 m/s^(2)` (5) This will be the acceleration of the object is the force is changed to 8 N.