Lab 15
The purpose of this lab is that by using a ball hit on the block and find out the the speed of the ball and uncertainty.
Apparatus:
Apparatus:
By using equipment, I am going to find the velocity of the ball when it hits the block and the uncertainty about it.
Using this equipment, because this equipment can shoot the ball with velocity, and hit and stick together with the block, and then the ball and the block will have some velocity and move up and down, and the height can be measure the by the angel which will be given by the stick.
the stick will show you the highest position the block get and we can read the angel on this equipment.
To begin this, set the pointer to zero, and put the trigger and the ball will shoot the block and it will appear the angle of height.
Measure the weight of ball and block, and string length, and read the angle of the pointer.
when it hit the block, it will stick with the block and then get up together.
so it's collision.
So to test the velocity of ball before hit the block, need to figure the height of the block went and using the convervation energy to find out the moment ball and block velocity and using collision find out the ball's velocity.
Using the angel and length of string we can easily get the how high the ball and block go up by using the energy conserved.
Then we find out the velocity of the ball and block.
However, it's not the velocity the ball before hit the block because they stick together and energy exchanged.
So using momentum which is conserved before and after Pi = Pf, and then calculate the initial velocity of ball.
To find the uncertainty, we use differential equation to derive them by parts and plug the numbers which are uncertainty of weight of ball and block, angle, and string of length.
That's how to find out the V and dv
after test it, only 3.22% uncertain. the result is good we can say.
Using this equipment, because this equipment can shoot the ball with velocity, and hit and stick together with the block, and then the ball and the block will have some velocity and move up and down, and the height can be measure the by the angel which will be given by the stick.
the stick will show you the highest position the block get and we can read the angel on this equipment.
To begin this, set the pointer to zero, and put the trigger and the ball will shoot the block and it will appear the angle of height.
Measure the weight of ball and block, and string length, and read the angle of the pointer.
so it's collision.
So to test the velocity of ball before hit the block, need to figure the height of the block went and using the convervation energy to find out the moment ball and block velocity and using collision find out the ball's velocity.
Using the angel and length of string we can easily get the how high the ball and block go up by using the energy conserved.
Then we find out the velocity of the ball and block.
However, it's not the velocity the ball before hit the block because they stick together and energy exchanged.
So using momentum which is conserved before and after Pi = Pf, and then calculate the initial velocity of ball.
To find the uncertainty, we use differential equation to derive them by parts and plug the numbers which are uncertainty of weight of ball and block, angle, and string of length.
after test it, only 3.22% uncertain. the result is good we can say.
Conclusion
For this lab, goal is to find out the velocity of the ball in a pendulum. Through measure the angel, string length, both masses then calculate the velocity of the ball and dv which is uncertainty, got the result is pretty close which is 3.22% uncertainty.
Your calculations look fine.
回复删除You could do a clearer job describing what the apparatus is.
You could also describe what you are doing in your calculations. You do the steps, but you give no explanation at all of what your are doing and why.
Your "audience" in another Physics 4A student. If your classmate looked at your lab they'd just see a lot of equations.