A stationary object is pushed with a force of 400N for 8s, resulting in its having a final velocity of 24m/s. What is its mass?

The mass of the object is 133.33 kg

Explanation:

From Newton's second law of motion

F = ma

Where F is the force

m is the mass

and a is the acceleration

From the question,

A stationary object is pushed with a force of 400N, that is F = 400N. To determine the mass of the object,

First, we will determine the acceleration.

From one of the equations of kinematics for linear motion,

v = u + at

Where v is the final velocity

u is the initial velocity

a is the acceleration

and t is time

We  can write that

v - u = at

Then, a = (v - u) / t

From the question,

t = 8s

v = 24m/s

u = 0 m/s (Since the object was stationary, that is, it was pushed from rest)

∴ a = (24m/s - 0m/s) / 8s

a = 24 / 8 = 3 m/s²

Therefore, acceleration is 3 m/s²

Now,

From F = ma

m = F / a

From the question

F = 400N

∴ m = 400N / 3m/s²

m = 133.33 kg

Hence, the mass of the object is 133.33 kg.  

the focus of lesson 1 is newton's first law of motion - sometimes referred to as the law of inertia. newton's first law of motion is often stated as. an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

explanation:

a and b sometimes have a positive value