Calculating Kinetic Energy: Golf Ball with Initial Speed of 55.4 m/s

In summary, a golf ball with a mass of 47.7 grams is hit from a tee with an initial speed of 55.4 m/s and rises to a height of 31.2 m. Ignoring air resistance, the kinetic energy of the ball at its highest point is 0 J. To determine its speed when it is 8.47 m below its highest point, the equations for kinetic energy and gravitational potential energy (U = mgh) are useful. It is important to note that mechanical energy (KE + PE) is conserved. Comparing the initial energy to the energy at the top, the ball loses kinetic energy as it gains potential energy.
  • #1
eanderson
21
0
A 47.7-g golf ball is driven from the tee with an initial speed of 55.4 m/s and rises to a height of 31.2 m. (a) Neglect air resistance and determine the kinetic energy of the ball at its highest point. (b) What is its speed when it is 8.47 m below its highest point?
 
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  • #2
What have you tried? You need to show some effort. What equations/concepts might apply here?
 
  • #3
K = (1/2)mv^2 and i need something to help deal with the height part
 
  • #4
Do you know about gravitational potential energy?
 
  • #5
U=mgh... 47.7(-9.8)31.2 =14584.754 = U or gravitational potential energy
 
  • #6
Mechanical energy (KE + PE) is conserved. Careful with units. (The mass is given in grams, not kg.)
 
  • #7
.0477(-9.8)(31.2) = -14.584752
 
  • #8
wouldnt kinetic be 0 at the highest point because all the energy is potential?
 
  • #9
eanderson said:
wouldnt kinetic be 0 at the highest point because all the energy is potential?
No. Only the vertical component of velocity is zero at the highest point--it's still moving horizontally.
 
  • #10
what do i do now?
 
  • #11
eanderson said:
what do i do now?
Compare the initial energy (KE + PE) at the start with the energy (KE + PE) at the top. The ball loses KE as it gains PE.
 

FAQ: Calculating Kinetic Energy: Golf Ball with Initial Speed of 55.4 m/s

1. What is kinetic energy?

Kinetic energy is the energy an object possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity.

2. How is kinetic energy calculated?

Kinetic energy is calculated using the formula KE = 1/2 * m * v^2, where m is the mass of the object and v is its velocity.

3. What are some examples of objects with high kinetic energy?

Objects with high kinetic energy include moving cars, airplanes, and projectiles such as bullets.

4. Can kinetic energy be transferred from one object to another?

Yes, kinetic energy can be transferred from one object to another through collisions or contact forces.

5. How does kinetic energy relate to potential energy?

Kinetic energy and potential energy are two forms of energy that are related through the law of conservation of energy. As an object loses potential energy, it gains kinetic energy and vice versa.

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