Download STAAR 8th Grade Physics Packet

Westrup
8th Grade Science STAAR Review
Name:_________________
Category 2: Force, Motion, and Energy 8th grade TEKS
The student will demonstrate an understanding of force, motion, and energy and their relationships.
TEKS 8.6A demonstrate and calculate how unbalanced forces change the speed or direction of an
object’s motion Readiness Standard
For each diagram, state the net force, the direction of motion, and whether it is a balanced or
unbalanced force acting on the box.
Net Force = __________ Direction of Motion = __________
Balanced or Unbalanced?
Net Force = __________ Direction of Motion = __________
Balanced or Unbalanced?
Net Force = __________ Direction of Motion = __________
Balanced or Unbalanced?
List 5 ways an unbalanced force will affect an object’s motion.
1. ___________________________
4. ___________________________
2. ___________________________
5. ___________________________
3. ___________________________
Each picture below shows 2 unbalanced forces acting on the car. The dashed arrow represents the
car’s original force used to move it. The solid arrow represents a second force that was applied to the
car later on.
1.
3.
2.
4.
For each picture, tell whether the second force will cause the car to speed up, slow down, change
direction or stop.
1.
2.
3.
4.
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Westrup
8th Grade Science STAAR Review
Name:_________________
Category 2: Force, Motion, and Energy 8th grade TEKS
Force Calculations – solve the problems below.
1. What is the formula used to calculate force? _______________
Fill in the force triangle.
2. A horse pulls a covered wagon with a mass of 2500 kg with an acceleration of 1.5 m/s2.
Calculate the force the horse uses to the nearest whole number.
3. A bullet with a mass of .2 kg is shot out of a rifle with 120 Newtons of force. What is the
acceleration of the bullet?
4. An object accelerates 15 m/s2 when a force of 135 N is applied to it. What is the mass of the
object?
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Westrup
8th Grade Science STAAR Review
Name:_________________
Category 2: Force, Motion, and Energy 8th grade TEKS
TEKS 8.6B differentiate between speed, velocity, and acceleration Supporting Standard
Match a definition and example for each of the following descriptions of motion.
a. m/s2
_____ _____ Speed
d. speed in a certain direction
b. m/s
_____ _____ Velocity
e. change in distance over an amount of time
c. m/s North
_____ _____ Acceleration
f. a change in velocity over time
For each of the following situations, tell whether speed, velocity, or acceleration is changing (Note: it
can be more than one).
Change in:
1. Slowing down to 10 mph
Speed/Velocity/Acceleration
2. Speeding up to 45 km/hr
Speed/Velocity/Acceleration
3. Maintaining your speed at 30 mi/hr in the same direction
Speed/Velocity/Acceleration
4. Staying at a speed of 5 mph as you turn a corner
Speed/Velocity/Acceleration
5. Walking at a constant speed as you walk in a circle
Speed/Velocity/Acceleration
True or False: When speed changes, so does velocity and acceleration.
True or False: When direction changes, speed, velocity, and acceleration all change.
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Westrup
8th Grade Science STAAR Review
Name:_________________
Category 2: Force, Motion, and Energy 8th grade TEKS
TEKS 8.6C investigate and describe applications of Newton’s law of inertia, law of force and acceleration,
and law of action-reaction such as in vehicle restraints, sports activities, amusement park rides, Earth’s
tectonic activities, and rocket launches Readiness Standard
Determine which of Newton’s 3 Laws matches with the correct description.
_____ Newton’s 1st Law
a. the law of action/reaction
_____ Newton’s 2nd Law
b. the law of inertia
_____ Newton’s 3rd Law
c. F = ma
Use your knowledge of Newton’s Laws of Motion to answer the questions below.
1. Two students are in a baseball game. The first student hits a ball very hard and it has a greater
acceleration than the second student who bunts the ball lightly. Which Law of Motion and why?
2. A magician pulls a tablecloth out from under dishes and glasses on a table without disturbing them.
Which Law of Motion and why?
3. A soccer player kicks a ball with their foot and their toes are left stinging. Which Law of Motion and
why?
4. A person not wearing a seatbelt flies through a car window when someone slams on the breaks
because the person’s body wants to remain in continuous motion even when the car stops. Which
Law of Motion and why?
5. Pushing a child on a swing is easier than pushing an adult on the same swing, because the adult has
more inertia. Which Law of Motion and why?
6. Rockets are launched into space using jet propulsion where exhaust accelerates out from the rocket
and the rocket accelerates in an opposite direction. Which Law of Motion and why?
7. A soccer ball accelerates more than a bowling ball when thrown with the same force. Which Law of
Motion and why?
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