A ball of mass 0.4 kg, initially at rest, is

kicked directly toward a fence from a point

20 m away, as shown below.

The velocity of the ball as it leaves the

kicker’s foot is 19 m/s at angle of 61 ◦ above

the horizontal. The top of the fence is 12 m

high. The kicker’s foot is in contact with the

ball for 0.04 s. The ball hits nothing while in

flight and air resistance is negligible.

The acceleration due to gravity is 9.8 m/s2

1. Determine the magnitude of the average

net force exerted on the ball during the kick.

Answer in units of N.

2. Determine the time it takes for the ball to reach the plane of the fence. Answer in units of s.

3. Hint: Consider the diameter of the ball to be

negligible. How far above the top of fence will the ball

pass? Answer in units of m.

4. What is the vertical component of the velocity

when the ball reaches the plane of the fence?

Answer in units of m/s.

I have gotten all of the parts except 3. I have tried submitting .969, 1.148, and .8377 nut they are all wrong

1 is 190

2 is 2.1739

4 is -4.68649

THESE THREE ARE RIGHT FOR SURE. I SUBMITTED THEM

kicked directly toward a fence from a point

20 m away, as shown below.

The velocity of the ball as it leaves the

kicker’s foot is 19 m/s at angle of 61 ◦ above

the horizontal. The top of the fence is 12 m

high. The kicker’s foot is in contact with the

ball for 0.04 s. The ball hits nothing while in

flight and air resistance is negligible.

The acceleration due to gravity is 9.8 m/s2

1. Determine the magnitude of the average

net force exerted on the ball during the kick.

Answer in units of N.

2. Determine the time it takes for the ball to reach the plane of the fence. Answer in units of s.

3. Hint: Consider the diameter of the ball to be

negligible. How far above the top of fence will the ball

pass? Answer in units of m.

4. What is the vertical component of the velocity

when the ball reaches the plane of the fence?

Answer in units of m/s.

I have gotten all of the parts except 3. I have tried submitting .969, 1.148, and .8377 nut they are all wrong

1 is 190

2 is 2.1739

4 is -4.68649

THESE THREE ARE RIGHT FOR SURE. I SUBMITTED THEM

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