Physics Calculations 10 steps
1st step: The potential energy of the earth being pulled up is 0.085 J. We solved this by using the equation , PE= mgh. m= 0.011 kg, g= 9.8 m/s, h= 0.78 m.
2nd step: 3.25 N of work is being used when the Earth is released from the rocket ship.
3rd step: The potential energy that is being decreased is 0.072 J. The potential energy decreases because the meteor is being dropped down from the wedge.
4th step: When rolling down the ramp the Earth has a velocity of 2.1 m/s. To find the velocity we used the equation, v= d/t. d= 1.05 m and t= 2 s.
5th step: The kinetic energy of the meteor when it falls from the hole onto the big dipper (lever) is 0.041 J. KE= 1/2 mv(2).
6th step: The potential energy of the star being launched is 0.14 J. We calculated this by using, PE+mgh. m= 0.04 kg, h= 0.37 m, g= 9.8 m/s.
7th step: The mechanical advantage of the screw that the star rolls on is 11 times easier. We solved this by finding the height from where the ball drops. 66 cm, 6 cm=11
8th step: The potential energy of the ball hitting the dominoes and causing them to fall is 0.047 J.
9th step: The velocity of Earth being released from the cage and falling is .38 m/s. we used v= d/t.
10th step: The velocity of Earth rolling down the last inclined plane is 0.14 m/s. we used the same equation as above to solve this.
Velocity: Velocity is the rate of covered distance in a direction. The equation for velocity is the change in distance/ the change in time. Speed is equal to velocity . In the project we used velocity to calculate a ball rolling down a ramp. we took the distance of the ramp and calculated how much time it took the ball to roll down the distance of the ramp. The distance of the ramp was 1.05 m and the time it took to roll down the ramp was 2 s. After we found the time and distance we divided the two to get the velocity of the ball which was 2.1 m/s.
Work: Work is the amount of energy put into doing something. The equation for work is work equals force times distance and the unit is Joules. Also a key thing we had to remember is if there is no distance than there is no work. In our second step we used the equation for work to find out how much work is being done when the Earth is released form the rocket ship. The earth when it was released took 3.25 Newtons of work.
Acceleration: Acceleration is the rate of change of velocity (how much it is speeding up or slowing down). To find the acceleration of the ball picking up speed when rolling down the ramp I used the equation change in velocity/ change in time. From previous calculations I had made I found that the velocity was 2.1 m/s and the time was 2 s. So I divided the velocity by time and got 1.05 m/s/s.
Force: A push or pull on an object, causes the change in motion. The equation for force is force equals mass times acceleration. (F=ma). The unit for force is N (Newtons). Example word problem to find force: The mass of a ball is 6 g what is the force of the ball rolling down the ramp? First you would need to convert grams to kilo grams. 6 g ( 1kg/1000 g)= 0.006 kg. Sense you do not have the acceleration you would need to use ag (acceleration due to gravity). The new equation would be F = MAg. Mass = 0.006 kg, and ag = 9.8 m/s/s. Then you would take the mass and acceleration due to gravity and multiply the two. F = 0.006 kg (9.8 m/s/s) = 0.058 newtons.
Mechanical Advantage:
There are two types of mechanical advantages, one of them is mechanical advantage real and the other is mechanical advantage ideal. Mechanical advantage real is how much easier (less) a tool makes a task. The equation for MA real is Ma real= F load/F effort. While mechanical advantage ideal is how much further (more distance) you have to push due to using a tool. The equation for MA ideal is MA ideal= d effort/d load. Although neither mechanical advantages have units because they are both ratios. You will normally use the equation for MA ideal and real when you are given a problem involving pulleys. To find the Ma advantage of a pulley you would count how many ropes there are and that will tell you what the MA advantage is. So if there were three ropes then MA would be equal 3.
Energy:
There are two main types of energy that we used throughout the project such as potential energy and kinetic energy. Potential energy is the energy an object has due to its position at a height or in a gravitational field. The equation for PE is Potential energy is equal to mass times gravity times height. The unit for PE is J (Joules). Lets say that I dropped a ball with a mass of 5 kg from 12 meters. In order to find the PE you would need to multiply the mass (5 kg) by the acceleration due to gravity (9.8 m/s/s). When you multiply the mass times acceleration due to gravity you would get a product of 49. Then you would Multiply 49 by 9.8 m/s/s to get potential energy equaling 480.2 J. Kinetic energy is energy due to motion. The equation for kinetic energy is KE = 1/2 mv squared. What would be the KE of the ball? The kinetic energy of the ball would be 480.2 J because the change in potential energy is equal to the change in kinetic energy. So the potential energy is transferred to the kinetic energy.