Download Forces and MotionTest

Mid Term Study Guide
8th Grade PSI Science
Name ____________________________________
Major Ideas:
1) What is a force?
2) What are the common units for force?
3) What is Newton’s 1st Law of Motion?
4) What is Newton’s 2nd Law of Motion?
5) What is Newton’s 3rd Law of Motion?
6) What is inertia?
7) What is acceleration?
8) What are the common units for acceleration?
9) What factors influence acceleration?
10) What is a net force?
11) What are electromagnetic forces?
12) What factors influence the amount of electromagnetic force?
13) Explain how electromagnetic forces can be either positive or negative.
14) What are gravitational forces?
15) What factors influence gravitational forces?
16) Explain how gravitational forces can only be positive.
17) What is the difference between a force and a field?
18) What is the purpose of a test particle in a field?
19) What do field lines indicate?
20) What information does the spacing of field lines provide?
21) What is kinetic energy?
22) What factors influence kinetic energy?
23) What are the common units for energy of all types?
24) What is gravitational potential energy?
25) What factors influence gravitational potential energy?
26) Explain Conservation of Energy.
27) How is temperature related to energy?
28) What are the common units for temperature?
29) How can the temperature of an object be increased?
30) What factors influence how much energy is needed to change the temperature of an
object?
31) What is heat?
32) What are the common units for heat?
33) How does heat flow between objects of different temperatures?
34) When does heat flow stop between two objects?
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Mid-Term Study Guide
Multiple Choice:
1) Which of the following represents a possible force?
a) 15.5m/s
b) 9.8m/s2
c) 25.4N
d) 7.2J
2) Which of the following represents a possible acceleration?
a) 15.5m/s
b) 9.8m/s2
c) 25.4N
d) 7.2J
3) Which of the following would cause acceleration?
a) no forces acting on an object
b) two equal but opposite forces acting on an object
c) two unequal but opposite forces acting on an object
d) none of the above
4) If a ball applies a force to a wall, what is true of the force applied by the wall on the ball?
a) the wall does not apply a force to the ball because the wall is not moving
b) the wall applies a smaller force to the ball because the wall is not moving
c) the wall applies a larger force to the ball because the wall has more mass
d) the wall applies an equal but opposite force to the ball
5) Which will have a higher acceleration, a 2.5kg box that is pushed with a net force of 50N
or a 2.5kg box that is pushed with a net force of 10N?
a) The 50N force
b) The 10N force
c) They will have the same acceleration
d) It depends on what is inside of the boxes
6) A person standing on a sidewalk sees you ride past on the school bus, but you feel as if
you are at rest while sitting in your seat. This is an example of __________________.
a) Freefall
b) Relative motion
c) Interpretative motion
d) Perspective motion
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Mid-Term Study Guide
7) For magnetic poles, which of the following is true?
a. South poles attract South poles
b. North poles attract North poles
c. South poles repel South poles
d. North poles attract South poles
8) What happens to the amount of force between two charged objects as the charge on one
of the objects gets bigger?
a. The force increases
b. The force decreases
c. The force becomes positive
d. The force becomes negative
9) What happens to the amount of gravitational force between objects as the distance
between the objects gets smaller?
e. The force increases
f. The force decreases
g. The force becomes positive
h. The force becomes negative
10) Which of the following is cannot be true?
a) The electromagnetic force is -10N.
b) The electromagnetic force is +10N.
c) The gravitational force is -10N.
d) The gravitational force is +10N.
11) Electric field lines are drawn _____________________.
a. Into both positive and negative charges
b. Out of positive charges and into negative charges
c. Out of negative charges and into positive charges
d. Out of both positive and negative charges
12) The right hand rule helps you determine the direction of a
wire carrying current.
a. Gravitational Field
b. Magnetic Field
c. Electric Field
d. All of the above
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surrounding a
Mid-Term Study Guide
13) When a ball is dropped from the top of a ladder, at what point does it have the most
gravitational potential energy?
a. the top, right when it is released
b. half way down
c. just before it hits the ground
d. after it stops bouncing and stays motionless
14) When a ball is dropped from the top of a ladder, at what point does it have the most
kinetic energy?
a. the top, right when it is released
b. half way down
c. just before it hits the ground
d. after it stops bouncing and stays motionless
15) When a ball is dropped from the top of a ladder, at what point does it have the least
kinetic energy?
a. the top, right when it is released
b. just before it hits the ground
c. after it stops bouncing and stays motionless
d. both a and c are correct
16) At which point does the ball have the largest amount of Total Energy?
a. the top
b. halfway down
c. just before it hits the ground
d. All points have the same Total Energy
17) How could you increase the velocity of the ball just before it hits the ground?
a. increase the mass of the ball
b. decrease the mass of the ball
c. use a taller ladder
d. use a shorter ladder
18) How could you decrease the total energy of the dropped ball?
a) increase the mass of the ball
b) decrease the mass of the ball
c) use a shorter ladder
d) both b and c are correct
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19) Which of the following is not a kind of energy?
a. Gravitational Potential
b. Temperature
c. Heat
d. Kinetic
20) Which of the following is not a temperature scale?
a. Calvin
b. Fahrenheit
c. Celsius
d. Kelvin
21) Which has more thermal energy 100mL of water at 50°C or 100mL of water at 25°C?
a. the water at 50°C
b. the water at 25°C
c. They have the same energy
d. It depends on how they were heated
22) Which has more thermal energy 200mL of water at 50°C or 300mL of water at 50°C?
a. the 200mL water
b. the 300mL water
c. They have the same energy
d. It depends on how they were heated
23) Which of the following is most likely to be the best conductor?
a. Copper
b. Air
c. Plastic
d. Styrofoam
24) Which of the following statements is true?
a. Heat flows from hot to cold
b. Cold flows from cold to hot
c. Heat flows from cold to hot
d. Cold flows from hot to cold
25) Why does the liquid in a thermometer shrink when the temperature is colder?
a. The thermometer absorbs heat from the surroundings
b. The molecules in the thermometer liquid are moving faster
c. The space between molecules decreases as they release heat
d. All of the above are true
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Mid-Term Study Guide
Free Response
1.
2.
3.
4.
A snail travels 10 m in 3000 seconds. What is the snail’s average speed?
A blimp travels at 3 m/s for 1000 s. What distance does the blimp cover in that time?
A 100 kg kid is on the moon, where g = 1.67 m/s2. What is the boy's weight?
What is the net force acting on the object below?
-10 N
7N
-8 N
5.
6.
7.
8.
Is the object in number 4 in equilibrium? Explain.
How can a) a mass, b) a positive charge, and c) a compass be used as field detectors?
Explain the process of induction.
How do electric field diagrams and magnetic field diagrams compare to each other for
attraction/repulsion? Explain your answer in a short paragraph.
9. What is the Kinetic Energy of a 1000 kg car that is traveling with a speed of 15 m/s?
10. What is the Gravitational Potential Energy of an object that has a mass of 5 kg and is at a
height of 10 m above the Earth's surface?
11. Explain how a Wind Turbine converts kinetic energy to electricity.
12. How are temperature and kinetic energy related?
13. Describe what happens to motion and spacing of molecules when heated or cooled for
a. liquid
b. solid
c. gas
14. What does a thermometer measure?
15. Describe characteristics of the three temperature scales including freezing and boiling
point of water for each.
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8th Grade PSI
Mid-Term Study Guide