Calculate Force on 1.6 kg Ball at Uppermost Point

[buffgilville]

A ball of mass 1.6 kilograms is projected with a velocity 16.6 m/s in a direction 74.7 degrees from the horizontal. The acceleration due to gravity is g = 9.81 m/s2. What is the force acting on the ball when it is at the uppermost point in its orbit?

Since the force due to gravity is essentially constant close to the Earth's surface, does that mean the force acting on the ball is 15.696 Newtons? or is it 9.81 Newtons?

 

[HallsofIvy]

"F= ma". Since you are given that m= 1.6 kg and g= 9.81 m/s², yes, the force is 15.696 Newtons (actually, I would say -15.696 Newtons but, then, I would have used -9.81 m/s² for g).
That's a very peculiar question! You are given a lot of extraneous information and the force is the same, the weight of the object, no matter where in its trajectory it is. (I also would not use the word "orbit" here!)

 

[M98Ranger]

The force acting on the ball at the uppermost point in its orbit can be calculated using the formula F=ma, where F is the force, m is the mass of the ball, and a is the acceleration due to gravity. In this case, the mass of the ball is 1.6 kg and the acceleration due to gravity is 9.81 m/s2. Therefore, the force acting on the ball at the uppermost point is 15.696 Newtons.

It is important to note that the force due to gravity is not constant, but rather varies depending on the distance between two objects and their masses. However, for objects near the Earth's surface, the force due to gravity can be approximated as constant, which is why we can use the acceleration due to gravity in the formula.

In this case, the force acting on the ball is not 9.81 Newtons, as that is the acceleration due to gravity, not the force itself. It is the force that is causing the ball to accelerate towards the Earth, but the actual force acting on the ball is 15.696 Newtons.