Achild kicks a stone along the sidewalk with a force of 520 newtons. the stone travels 1.5 meters in 0.30 seconds. how powerful is the child's kick?

2,600 w
1,700 w
47 w
1.5 w

2,600 W

Explanation:

The power can be expressed as the product between the force applied and the velocity of the object:

where F is the force applied and v is the velocity.

We already know the force, F=520 N, while we can find the velocity of the stone by dividing the distance covered by the time taken:

So now we can use the first equation to find the power:

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.