A single force of 40 N acts upon a 5-kg block. What is the magnitude of the acceleration of the block?

#a=8" m"//"s"^2#

Explanation:

Sounds like a job for Newton's second law.

In summary, this law of motion states that the acceleration of an object is proportional to, and in the same direction as, the net force acting on the object, as well as inversely proportional to the mass.

This gives the familiar equation:

#color(blue)(vecF_"net"=mveca)#

We are given a force and a mass and we want an acceleration. We'll have to use a bit of algebra.

#F=ma#

#=>color(blue)(F/m=a)#

Given #F=40"N"# and #m=5"kg"#, we have:

#a=(40"N")/(5"kg")#

#=>color(blue)(a=8" m"//"s"^2)#