Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Science exam part 2
| Question | Answer |
|---|---|
| What happens to the momentum of 2 billiard balls that collide? | the momentum will be conserved. Momentum will be the same before and free the collision. |
| why do planets orbit the sun instead of traveling into space? | force of gravity between the sun and planets provides the centripetal force that keeps the planets in orbit. |
| What Is weight? | Force of gravity exerted on an object |
| how do you calculate weight if you are given a mass? | w=mg |
| acceleration due to gravity on earth is_____ | 9.8m/s2 |
| as_____ increases the grav. Force increases | mass |
| As_____ between 2 objects increases grav. Force increases | distance |
| newton’s 1st law | an object in motion or at rest stays that way, unless acted on by an outside force |
| newton’s 2nd law | net force acting on an object os equal to the object’s mass times acceleration |
| newton’s 3rd law | every action has an equal and opposite reaction |
| newton’s 1st law is often called the law of___ | inertia |
| Formula describing relationship between force ,mass, and acceleration | Fnet=MA |
| What happens when you kick a soccer ball? | an outside force is applied by the foot to the ball causing it to accelerate |
| why does a person to wearing a seatbelt will likely hit the windshield in a collision? | without a seatbelt to apply a force to a person, he will continue moving t that same speed until an outside force acts on it. |
| must an object with balanced forces be at rest? | no, an object could be moving at a constant speed and the forces would be balanced. |
| What cause a feather to fall more slowly than a brick? | air resistance |
| what would happen without the presence of air? | feather and brick will fall at same rate |
| what can affect air resistance? | surface area |
| explain purpose of a parachute | to increase air resistance by increasing surface area |
| an apple hanging on a tree has___ | gravitational chemical potential energy |
| _____and_____ must happen for work t be done | force applied and distance moved |
| ______ make work easier | machines |
| List types of simple machines: | wheel and axle, inclined plane, lever, pulley, wedge, screw |
| combination of 2 or more simp. Machines | compound machine |
| rate at which energy is transformed | power |
| according to the____ the universes total energy does not change | law o conservation of energy |
| a stretched rubber band has | elastic potential energy |
| energy in motion and stored energy due to position | mechanical energy |
| As you ride on a swing, your energy is converted from ____to____ and back again | gpe, ke |
| on a swing, where is gpe the highest? | at highest point |
| where is KE the highest? | longest point |
| unit used to measure how much energy you get from food | calorie |
| kinetic energy is measured in____ | joules |
| gpe is measured in _____ | joules |
| how does friction affect the mechanical energy of a system? | Friction converts me into te |
| What is the formula for work? | w=fd (J) (N) (M) |
| formula for mechanical advantage | ma=Fout/Fin (N/N) |
| formula for efficiency | eff=Wout/Win x 100 % (J/J) |
| formula for kinetic energy | ke=1/2mv2 (J) (Kg) (M/s) |
| formula for gravitational potential energy | GPE=mgh (J) (Kg) (M/s2) (M) |
| formula for power | p=w/t or e/t (W) (J/S) |
| How much work is done by the boy carrying a 20 kg box across the room and horizontal distance of 10 m? | no work is done since the force applied and distance moved are perpendicular |
| a book is sliding across a horizontal table slows down and comes to a stop. The books kinetic energy was converted into what form of energy? | thermal energy |
| transfer of TE through direct contact ( stove to pot) | conduction |
| transfer of TE through the movement of warmer and cooler fluids or gases (boiling water) | convection |
| A ____ is a device that converts TE into ME | heat engine |
| TE is transferred slowly through an____ | insulator |
| Metals are good____of TE | conductors |
| as speed of particles increases , the temp ____as speed particles increases a substance decreases the temp____ | increases , decreases |
| TE is measure in____ | joules |
| In order for heat to flow from a cooler area to a warmer area _____ must be done. Give an example of A device thats does this | work, fridge |
| a coolant is a substance that_____ | has a high specific heat.it can absorb a lot of TE without much change in temp. |
| temp is measured in____in metric system. The base SI unit for temperature is _____ | celcius, kelvin |
| heat naturally moves from an area of ____ temp to an area of___temp | higher, lower |
| What is water used as a coolant? | It has a high specific heat, so it can absorb a lot of TE without much change in temp. |
| how does a thermos work? | to minimize TE transfer by conduction + convection a thermos has a vacuum between 2 walls. Conduction + convection both require matter to transfer TE, and there is no matter in a vacuum. It is made of reflective materials and it reflects radiation. |
| does insulation in the attic keep cold out in the winter? | it slows down the heat transfer through roof to outside cooler air. |
| which has the greater amount of TE, one liter of water at 50 degree celcius or 2 liters of water at 50 degree celcius? | 2 liters |
Created by:
Caydee $mith