John Lester is at the park practicing his pitching. Since he doesn’t have a catcher, John wants to pitch the ball all the way around the Earth so he can catch it himself. Neglecting air drag and any obstacles that might be in the way, about how fast must the ball be moving? You may take the radius of the Earth to be 6400 km.

Explanation:

Let assume that John Lester has a height of 1.80 meters and throws the ball at 70 percent of John Lester's height. The time before the ball hits the soil is:

The initial horizontal velocity required to pitch the ball all the way around the Earth is:

im sorry i dont know

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.