What equations do I use to solve this?

  • Thread starter crhscoog
  • Start date
In summary, a ball of mass .5kg is kicked towards a fence from a distance of 32 meters. It has an initial velocity of 20m/s at an angle of 37 degrees above the horizontal and is in contact with the kicker's foot for .05 seconds. The top of the fence is 2.5m high and there is no air resistance. The magnitude of the average net force exerted on the ball during the kick needs to be determined, as well as the time it takes for the ball to reach the fence. It is also asked whether the ball will hit the fence and if so, how far below the top of the fence it will hit. If not, how far above the top of the fence
  • #1
crhscoog
17
0

Homework Statement



A ball of mass .5kg, initially at rest, is kicked directly toward a fence from a point 32 meters away, as shown above. The velocity of the ball as it leaves the kicker's foot is 20m/s at an angle of 37 degrees above the horizontal. The top of the fence is 2.5m high. The kicker's foot is in contact with the ball for .05 second. The ball hits nothing while in flight and air resistance is negligible.

a. Determine the manitude of the avg net force exerted on the ball during the kick.

b. Determine the time it takes for the ball to reach the plane of the fence.

c. Will the ball hit the fence? If so, how far below the top of the fence will it hit? If not, how far above the top of the fence will it pass?
 
Physics news on Phys.org
  • #2
crhscoog said:

Homework Statement



A ball of mass .5kg, initially at rest, is kicked directly toward a fence from a point 32 meters away, as shown above. The velocity of the ball as it leaves the kicker's foot is 20m/s at an angle of 37 degrees above the horizontal. The top of the fence is 2.5m high. The kicker's foot is in contact with the ball for .05 second. The ball hits nothing while in flight and air resistance is negligible.

a. Determine the manitude of the avg net force exerted on the ball during the kick.

b. Determine the time it takes for the ball to reach the plane of the fence.

c. Will the ball hit the fence? If so, how far below the top of the fence will it hit? If not, how far above the top of the fence will it pass?
You seem to have missed out a couple of important sections:

Homework Equations





The Attempt at a Solution

 
  • #3


The equations you would use to solve this problem are the equations of motion. These include:

1. Equation for average net force: F = m * a, where F is the force exerted, m is the mass of the object, and a is the acceleration.

2. Equation for acceleration in the x-direction: a_x = (F_x)/m, where a_x is the acceleration in the x-direction, F_x is the force exerted in the x-direction, and m is the mass of the object.

3. Equation for acceleration in the y-direction: a_y = (F_y)/m, where a_y is the acceleration in the y-direction, F_y is the force exerted in the y-direction, and m is the mass of the object.

4. Equation for velocity in the x-direction: v_x = v_0 * cos(theta), where v_x is the velocity in the x-direction, v_0 is the initial velocity, and theta is the angle of the initial velocity.

5. Equation for velocity in the y-direction: v_y = v_0 * sin(theta) - g * t, where v_y is the velocity in the y-direction, v_0 is the initial velocity, g is the acceleration due to gravity (9.8 m/s^2), and t is the time.

6. Equation for displacement in the x-direction: x = x_0 + v_0 * cos(theta) * t, where x is the displacement in the x-direction, x_0 is the initial position, v_0 is the initial velocity, theta is the angle of the initial velocity, and t is the time.

7. Equation for displacement in the y-direction: y = y_0 + v_0 * sin(theta) * t - 1/2 * g * t^2, where y is the displacement in the y-direction, y_0 is the initial position, v_0 is the initial velocity, theta is the angle of the initial velocity, g is the acceleration due to gravity, and t is the time.

Using these equations, you can solve for the magnitude of the average net force (a), the time it takes for the ball to reach the plane of the fence (b), and whether or not the ball will hit the fence and at what height (c). You will also need to use the trigonometric functions cosine and sine to calculate the x and y components of the
 

1. What are the basic equations used in physics?

The basic equations used in physics include Newton's laws of motion, the laws of thermodynamics, and the laws of electromagnetism. These equations form the foundation of our understanding of the physical world and are used to explain a wide range of phenomena.

2. How do I know which equation to use to solve a specific problem?

The equation(s) you need to use will depend on the specific problem you are trying to solve. It is important to first understand the concepts and principles behind the problem, and then identify which equations are relevant to those concepts. It may also be helpful to consult a textbook or ask a teacher or tutor for guidance.

3. Can I use different equations to solve the same problem?

Yes, there are often multiple equations that can be used to solve the same problem. However, you should choose the equation that is most relevant and appropriate for the specific problem at hand. It is also important to double check your work and make sure your final answer makes sense in the context of the problem.

4. Do I need to memorize all the equations in order to solve physics problems?

No, it is not necessary to memorize all equations in order to solve physics problems. It is more important to understand the concepts and principles behind the equations and how they relate to each other. With practice, you will become familiar with the most commonly used equations and will be able to easily identify which ones to use in a given situation.

5. Are there any tips for effectively using equations to solve problems?

One tip for effectively using equations to solve problems is to always double check your units and make sure they are consistent throughout the problem. It can also be helpful to draw diagrams or make a list of known and unknown variables to better understand the problem. Additionally, breaking the problem down into smaller, more manageable steps can make it easier to apply the appropriate equations.

Similar threads

  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
3
Views
9K
  • Introductory Physics Homework Help
Replies
5
Views
14K
  • Introductory Physics Homework Help
Replies
1
Views
3K
  • Introductory Physics Homework Help
Replies
7
Views
3K
  • Introductory Physics Homework Help
Replies
11
Views
6K
  • Introductory Physics Homework Help
Replies
2
Views
848
  • Introductory Physics Homework Help
Replies
2
Views
19K
  • Introductory Physics Homework Help
Replies
3
Views
2K
  • Introductory Physics Homework Help
Replies
7
Views
3K
Back
Top