Unit 4 Test (Least Learned Skills)

The picture shows Haile's paper airplane flying through the air.

Haile's plane travels forward for a few feet and then begins to fall. What would explain the plane's ability to travel forward for a few feet without falling?

• The speed of the plane is equal to the speed of the oncoming air that pushes on the

  plane.

• The speed of the plane is greater than the speed of the oncoming air that pushes on

  the plane.

• The force of the air pushing up on the plane is equal to the force of gravity pulling

  down on the plane.

• The force of gravity pulling down on the plane is greater than the force of the air

  pushing up on the plane.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

A student is planning two experiments. Both experiments will observe how a ping pong ball moves when placed in front of an electric fan that blows air. The image shows the student's setup and the supplies she has available. In her first experiment, she would like to explore the question, "How does an object's motion change when the force placed on the object changes?" In her second experiment, she would like to explore the question, "How does an object's motion change when the mass of the object changes?" She plans to test these questions by turning the fan on and off for 10 seconds at a time, changing the speed of the fan, and using ping pong balls with two different masses.

Which statement correctly describes the independent and dependent variables in the second experiment?

• The independent variable is the mass of the ping pong ball. The dependent variable is the distance the ping pong ball travels.

• The independent variable is the distance the ping pong ball travels. The dependent variable is the mass of the ping pong ball.

• The independent variable is the speed of the fan. The dependent variable is the distance the ping pong ball travels.

   

• The independent variable is the distance the ping pong ball travels. The dependent variable is the speed of the fan.

Tags

NGSS.MS-PS2-2

Which of the following statements is TRUE?

• Unbalanced forces have a net force of zero.

• Balanced forces do not have a net force of zero.

• Unbalanced forces do not cause movement, and balanced forces cause movement.

• Unbalanced forces cause movement, and balanced forces do not cause movement.

A bowling ball is moving down a flat bowling lane at a constant speed. Which statements best describe the movement of this bowling ball? Select all that apply.

• Its movement is caused by unbalanced forces.

• Its movement changes without a force acting upon it.

• Its movement shows Newton's first law of motion.

• Its movement shows Newton's third law of motion.

The driver of a car completes a trip. The graph displays data about the car's motion during the trip. Which of the following statements about the car's motion is true?

• The total time for the car trip was 50 minutes.

• The car returned to where it had started the trip at the end of the trip.

• The car did not slow down during the trip.

• The car did not travel at a constant speed during the entire trip.

The graph shows a bicycle rider's motion during the first portion of a race. What conclusion can be drawn about the rider's motion?

• The rider maintained a constant speed during the time period between 0 and 10 seconds.

• The rider did not move during the time period between 10 and 15 seconds.

• The rider rode downhill during the time period between 15 and 20 seconds.

• The rider slowed down during the time period between 15 and 20 seconds.

Tags

NGSS.MS-PS3-1

NGSS.MS-PS3-5

A student's class competes in a game of tug-of-war at field day. The student observes that in tug-of-war, each team tries to pull the rope over to its side, and the team that pulls the other over first is the winner. The student decides to set up an investigation to study the forces involved in tug-of-war.

Investigation 1: The student finds a rolling cart weighing 50 kilograms and places it on a wooden surface. A rope is attached to both sides of the cart. In the first trial (Trial 1), the cart is pulled with three children each on either side, with each child applying the same force. In the second trial (Trial 2), the cart is pulled with three children on one side and two children on the other.

• 
  the motion of the cart

• the weight of the cart

• the force applied by the children

• the number of children pulling the rope

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

The graph shows the distance an object travels over time. Which table correctly describes the object's motion during each interval of time?

• 
• 
• 
• 

Tags

NGSS.MS-PS3-1

A water rocket uses an amount of water and pressurized air to send a plastic rocket several feet into the air. As the water and air rush out the tail end of the rocket, the rocket shoots into the air.

Which statement explains the rocket's motion?

• The inertia of the water and air must be overcome.

• The force of gravity of the rocket is greater than the water.

   

• The force of gravity must be overcome to achieve lift.  

• For every action there is an equal and opposite reaction.

A balloon rocket is made by attaching a balloon to a straw with tape. The straw is threaded onto a wire that is stretched across a room. When the air is released, the balloon travels in a direction opposite to the air flow, as shown. Two investigations are planned with the balloon rockets. In the first investigation, a regular balloon rocket will be tested and a balloon rocket with five pennies attached to it will be tested. In the second investigation, two balloons will be attached to the same straw, facing each other. The air in these two balloons will be released at the same time. The supplies available for each investigation are shown. Which of the following describes how the forces in the experiment can be controlled?

• Each balloon can travel the same distance each time.

• The number of pennies on the balloon can be counted.

• The same straw and wire can be used for each investigation.

• Each balloon can be filled with the same number of pumps of air.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2