What is the final velocity of the ball?

In summary, a ball with an initial velocity of 10 m/s and a mass of 3.00 kg hits a wall at a 60 degree angle and leaves the wall at a 60 degree angle. The goal is to find the force exerted by the wall on the ball. Using the equation p = mvcos(angle) and the given values, p1 is calculated to be 14.7N and p2 is calculated to be 14.1N. Taking into account the time of impact, the final force exerted by the wall on the ball is calculated to be 71.6N.
  • #1
rzlblrt417
9
0

Homework Statement



a ball hits a wall at 60 degrees from the wall and leaves the wall at 60 degrees.

v1 = 10 m/s
v2 = 10 m/s
m = 3.00 kg
t = 0.200s

Homework Equations



p = mvcos(angle)
J = p2 - p1


The Attempt at a Solution



p = (3.00)(10)(cos(60))
p1 = 15
p2 = 15

and that is as far as i can get. I am not sure how time plays into this. Any help is appreciated. I have the text in a few hours. Thank you
 
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  • #2
what is being asked for?
 
  • #3
rzlblrt417 said:

Homework Statement



a ball hits a wall at 60 degrees from the wall and leaves the wall at 60 degrees.

v1 = 10 m/s
v2 = 10 m/s
m = 3.00 kg
t = 0.200s

Homework Equations



p = mvcos(angle)
J = p2 - p1


The Attempt at a Solution



p = (3.00)(10)(cos(60))
p1 = 15
p2 = 15

and that is as far as i can get. I am not sure how time plays into this. Any help is appreciated. I have the text in a few hours. Thank you


As grzz said , I cannot understand what you are trying to find out. Anyways what's the question asking for ?
 
  • #4
My apologies, I always do that. Force on by the wall on ball
 
  • #5
*by wall on the ball
 
  • #6
rzlblrt417 said:
*by wall on the ball

Got that ! Ok so what is p1 ? Or I mean momentum of the ball before striking the wall ?

Then you find out p2 or the momentum of ball after it stroke the wall.

What do you get ?
 
  • #7
sankalpmittal said:
Got that ! Ok so what is p1 ? Or I mean momentum of the ball before striking the wall ?

Then you find out p2 or the momentum of ball after it stroke the wall.

What do you get ?

the same thing for p1 as p2?
 
  • #8
14.7n?
 
  • #9
rzlblrt417 said:
the same thing for p1 as p2?

No p1 and p2 aren't same. Be careful regarding geometry.

Hint : see the image : http://postimage.org/image/qvnhzhnsl/ [Broken]

Above answer is wrong.
Look at image
 
Last edited by a moderator:
  • #10
sankalpmittal said:
No p1 and p2 aren't same. Be careful regarding geometry.

Hint : see the image : http://postimage.org/image/qvnhzhnsl/ [Broken]

ok so then

p1 = (3.00)(10)cos(30)
p2 = (3.00)(10)cos(60)

so p2 - p1 = -14.133 so then it would just be 14.133N?

or is it sin(30) making it 14.5N
 
Last edited by a moderator:
  • #11
rzlblrt417 said:
ok so then

p1 = (3.00)(10)cos(30)

Correct.

p2 = (3.00)(10)cos(60)

Right !

so p2 - p1 = -14.133 so then it would just be 14.133N?

or is it sin(30) making it 14.5N

Nope. What about time t ?
From Newton's second law : F= Δp/Δt = p1-p2/t

Plug in it. What do you get ?
Do calculations properly. You got it wrong for p1-p2 also.
 
  • #12
sankalpmittal said:
Correct.



Right !



Nope. What about time t ?
From Newton's second law : F= Δp/Δt = p1-p2/t

Plug in it. What do you get ?
Do calculations properly. You got it wrong for p1-p2 also.

OH! ok so then after plugging everything in i got 71.6N!
 
  • #13
rzlblrt417 said:
OH! ok so then after plugging everything in i got 71.6N!

Your method of evaluation is correct but calculations are wrong. Do you know the value of cos 60o and cos 30o ? What are they ?
 

1. How does the speed of each ball affect the outcome of a collision?

The speed of each ball plays a significant role in determining the outcome of a collision. The faster a ball is moving, the greater its momentum and kinetic energy, which can result in a more forceful collision. This can lead to a larger change in direction or velocity for both balls involved.

2. What is the difference between an elastic and an inelastic collision?

In an elastic collision, both balls retain their original shapes and no kinetic energy is lost. This means that the total kinetic energy before and after the collision remains the same. In an inelastic collision, the balls may deform or stick together, and some kinetic energy is lost in the form of heat or sound. This results in a decrease in the total kinetic energy after the collision.

3. How does the angle of collision affect the final velocities of the balls?

The angle of collision between two balls can greatly impact the resulting velocities. If the balls collide head-on, the final velocities will be equal but in opposite directions. However, if the collision occurs at an angle, the final velocities will be split into two components: one parallel to the line of collision and one perpendicular to it. The angle of collision also affects the amount of kinetic energy transferred between the balls.

4. Can two balls with different masses have the same final velocity after a collision?

Yes, in a perfectly elastic collision, two balls with different masses can have the same final velocity if the lighter ball has a higher initial velocity. This is because the kinetic energy transferred between the balls depends on their relative masses and velocities, rather than their individual masses.

5. What factors can influence the outcome of a ball collision?

Several factors can affect the outcome of a ball collision, including the masses, velocities, and angles of the balls involved, as well as the elasticity of the balls and the surface they are colliding on. Other external factors such as air resistance and friction can also play a role in determining the final outcome.

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