Need Help with Momentum and Impulse? Need some one smart

In summary, to solve for the average force in the first question, we need to use the impulse formula (I=Δp) and substitute in the given values to solve for the force. In the second question, we need to find the change in momentum and then use the impulse formula to solve for the force.
  • #1
devilz_krypt
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Need Help with Momentum and Impulse?? Need some one smart...

The only formulas that were provided were

1. I =Δp
2. mΔv
3. I=FΔt
4. KE= 1/2 mv^2
5. PE= mgΔh
6. ΔPE= ΔKE
7. W= F*D
8. W= ΔKE

Momentum Before Collision = Momentum After Collision

9. m`av`a + m`bv`b = m`av`a + m`bv`b Elastic Collision
10. m`av`a + m`bv`b = m`av`b(v) inelastic collision

The little apostrophe are for subscripts, e.g. m`a, meaning "m" is normal, but the a is a subscript.


Questions
1. A tennis ball may leave the racket of a top player on the serve with a speed of 65 m/s. If the ball's ,*** is .06 kg and it is in contact with the rackt for .03 secs, what is the average force on the ball?

2. A .145 kg basball pitched at 39 m/s is hit on a horzontal line drive straight back towards the pitcher at 52 m/s. If the contact time betwween bat and ball is 1.00 E-3 sec, calculate the average force between the bat and ball contact.
 
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  • #2


1) You know the ball starts off at rest, and is then given a hit, which leads to a change in momentum. Impulse is a change in momentum; substitute and use that with the impulse formula to solve for force.

2)Yet again, solve for the change in momentum. Once found, set equal to I=FΔt
 
  • #3




Hello, it seems like you are struggling with understanding momentum and impulse. Don't worry, I can help you with that! Let's start with defining momentum and impulse.

Momentum is a measure of an object's motion and is calculated by multiplying its mass and velocity. It is a vector quantity, meaning it has both magnitude and direction. The unit for momentum is kg*m/s.

Impulse, on the other hand, is the change in momentum of an object and is calculated by multiplying force and time. It is also a vector quantity and has the same unit as momentum, kg*m/s.

Now, let's look at the formulas provided. The first two formulas, I = Δp and mΔv, are used to calculate impulse. The third formula, I = FΔt, is the same as the second one but written in a different form. The fourth and fifth formulas, KE = 1/2 mv^2 and PE = mgΔh, are used to calculate kinetic and potential energy respectively. The sixth formula, ΔPE = ΔKE, shows the relationship between potential and kinetic energy. The seventh and eighth formulas, W = F*D and W = ΔKE, are used to calculate work and work-energy theorem respectively.

Moving on to the questions you provided, let's solve them using the formulas and concepts we just discussed.

1. To calculate the average force on the tennis ball, we can use the formula I = FΔt, where I is the impulse, F is the force, and Δt is the contact time between the ball and racket. We know the mass of the ball (m = 0.06 kg), the initial velocity (v = 65 m/s), and the contact time (Δt = 0.03 s). So, we can rearrange the formula to solve for force: F = I/Δt = mΔv/Δt. Plugging in the values, we get F = (0.06 kg)(65 m/s)/0.03 s = 130 N. Therefore, the average force on the ball is 130 N.

2. To calculate the average force between the bat and ball contact, we can use the same formula I = FΔt. We know the mass of the ball (m = 0.145 kg), the initial and final velocities (v1 = 39 m/s and v2
 

1. What is momentum and how is it calculated?

Momentum is a measure of an object's motion and is calculated by multiplying its mass by its velocity. The formula for momentum is p = mv, where p is momentum, m is mass, and v is velocity.

2. What is the difference between momentum and impulse?

Momentum is a measure of an object's motion, while impulse is a measure of the force applied to an object over a period of time. Momentum is a vector quantity while impulse is a scalar quantity.

3. How is impulse related to momentum?

Impulse is the change in an object's momentum and is equal to the force applied to the object multiplied by the time it is applied. The formula for impulse is J = FΔt, where J is impulse, F is force, and Δt is the time interval.

4. How do you calculate the change in momentum?

The change in momentum can be calculated by subtracting the initial momentum from the final momentum. The formula for change in momentum is Δp = pf - pi, where Δp is the change in momentum, pf is the final momentum, and pi is the initial momentum.

5. Can you give an example of how momentum and impulse are used in real life?

One example is in sports, such as when a soccer player kicks a ball. The player's foot applies a force to the ball over a period of time, resulting in an impulse that changes the ball's momentum and causes it to move. Another example is in car accidents, where the force of impact and the time it is applied can affect the change in momentum and the severity of the collision.

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