7th Grade Chemistry and Physics (Period 7A) Assignments

Homework: Newton’s Laws of Motion

Which law of motion is being demonstrated in the following situations?

A. First Law of Motion
B. Second Law of Motion
C. Third Law of Motion

_______1. A magician pulls a tablecloth out from under dishes and glasses on a table without disturbing them.

_______2. A person’s body is thrown outward as a car rounds a curve on a highway.

_______3. Rockets are launched into space using jet propulsion where exhaust accelerates out from the rocket and the rocket accelerates in an opposite direction.

_______4. A picture is hanging on a wall and does not move.

_______5. 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.

_______6. Pushing a child on a swing is easier than pushing an adult on the same swing, because the adult has more inertia.

_______7. A soccer ball accelerates more than a bowling ball when thrown with the same force.

_______8. A soccer player kicks a ball with their foot and their toes are left stinging.

_______9. A student leaves a pencil on a desk and the pencil stays in the same spot until another student picks it up.

_______10. 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.

 

Homework: Momentum and Collision

 

A small rubber ball is thrown at a heavier, larger basketball that is still. The small ball bounces off the basketball. Assume there are no outside forces acting on the balls.

 

a. How does the force on the small ball compare to the force of the basketball?

 

 

b. Compare the total momentum of the two balls before and after collision.

 

Homework: Gravitational Force

 

Solve the following problems. Show your work. No work, no credit. 

 

1. What is the mass of an object with a weight of 35 newtons? Assume the object is on Earth’s surface.

 

 

 

2. The mass of a bag of potatoes is 0.5 kg. Calculate the weight of that potatoes in newtons.

 

Homework: Friction

 

A. Name three devices or inventions that are designed to decrease friction.

 

 

 

B. Name three devices or inventions that are designed to increase friction.

 

Lab Safety Sign 

1. Create a Lab Safety Sign.

2. Size 8.5" x 11" paper. 

3. Illustration should correctly display the lab safety rule 

4. The sign should be neatly done. 

5. Be creative and make sure your work is original (not copied) 

 

Grading Rubric (20 points) 

1. Illustration correctly display the lab safety rule       5       4        3        2        1  

2. Student demonstrate understanding of the rule     5       4        3        2        1

3. The sign is neatly done                                          5       4        3        2        1

    (Color in the lines, few eraser marks)

4. Creativity and Originality                                        5       4        3        2        1