Question

A 100-N force causes an object to
accelerate at 2 m/s/s. What is the
mass of the object?

Answer 1

`50\; \rm kg`.

Step-by-step explanation:

By Newton's Second Law, the acceleration
`a` of an object is proportional to the net force
`\sum F` on it. In particular, if the mass of the object is
`m`, then

`\sum F = m \cdot a`.

Rewrite this equation to obtain:

`\displaystyle m = (\sum F)/(a)`.

In this case, the assumption is that the
`100\; \rm N` force is the only force that is acting on the object. Hence, the net force
`\sum F` on the object would also be

Make sure that all values are in their standard units. Forces should be in Newtons (same as
`\rm kg \cdot m \cdot s^(-2)`, and the acceleration of the object should be in meters-per-second-squared (
`\rm m \cdot s^(-2)`). Apply the equation
`\displaystyle m = (\sum F)/(a)` to find the mass of the object.

`\displaystyle m = (100\; \rm N)/(2\; \rm m \cdot s^(-2)) = 50\; \rm kg`.