Force Pairs Review

On November 12, 2014, the Philae Lander touched down on comet 67P/C.G. Unfortunately, it bounced after the initial collision instead of clinging to the surface as planned. Which of the following are true about the force involved in collision?

• The forces in the collision were in the same direction.

• The comet exerted more force on the lander because it has more mass.

• The lander exerted more force on the comet because action forces always have more magnitude than reaction forces.

• The force exerted by the comet was equal and opposite to the force exerted by the lander.

Tags

NGSS.MS-PS2-1

Two cars of different masses collide head-on in a demolition derby. Both cars traveled with the same acceleration prior to the collision. Car A has twice the mass of car B. If car A exerts a force of 1000 Newtons in the collision, what is the force that car B exerts?

• 500 N

• 1000 N

• 2000 N

• 4000 N

Answer explanation

force is always EQUAL

Tags

NGSS.MS-PS2-1

A baseball player hits a baseball with a bat during a game. If the force exerted by the ball on the bat is 16,000 N, how would the magnitude force exerted by the bat on the ball compare?

• The bat would exert a force equal to the force of the ball on the bat.

• The bat would exert a force greater than the force of the ball on the bat.

• The bat would exert a force smaller than the force of the ball on the bat.

• The bat would exert a force of zero to balance the force of the ball on the bat.

Tags

NGSS.MS-PS2-1

Student A weighs 75 pounds, and Student B weighs 50 pounds. Student A gives Student B a push while standing on a skateboard as shown in the diagram. After the push, Student A moves backward while Student B remains motionless. Which statement is true?

• Neither student exerted a force on the other.

• Student B exerted a larger force compared to Student A.

• Student A exerted a larger force compared to Student B.

• Each student exerted an equal force on the other.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

A student observes the actions in four figures (1, 2, 3, and 4) and classifies each in a table. Which figures should the student classify as examples of Newton’s third law of motion?

• Figures 1 and 3 only

• Figures 1 and 4 only

• Figures 1, 2, and 4

• Figures 2, 3, and 4

Answer explanation

Arrows are equal length (strength) but in opposite directions

Tags

NGSS.MS-PS2-1

A student reads two examples regarding action and reaction forces and lists several patterns about the forces. Which pattern listed in the box above is incorrect?

• 1

• 2

• 3

• All are incorrect

Answer explanation

1 is incorrect because there are always TWO objects (force PAIRS)

Tags

NGSS.MS-PS2-1

Two students are testing the motion of an inflated balloon as air is released from it. They tape the balloon to a straw and insert a string through the straw. The string is tied to two poles. Which concept explains why the balloon moves along the string when air is released from the balloon?

• action and reaction

• friction

• inertia

• speed and acceleration

Tags

NGSS.MS-PS2-1

A student releases the air from an inflated balloon. As the air is released, the balloon moves forward. How can the student best classify the action and reaction forces of the balloon according to Newton’s third law of motion?

• Action: Air pushes balloon to the left, Reaction: Balloon pushes air to the right

• Action: Air pushes balloon to the right, Reaction: Balloon pushes air to the right

• Action: Balloon pushes air to the left, Reaction: Air pushes balloon to the right

• Action: Balloon pushes air to the right, Reaction: Air pushes balloon to the left

Tags

NGSS.MS-PS2-1

A student drops a basketball onto the floor. According to Newton's 3rd law, why does the ball bounce?

• The student dropped the ball

• The earth pulls the ball down

• The ball presses down on the floor

• The floor presses up on the ball

Tags

NGSS.MS-PS2-1

Considering Newton's 3rd Law, what force value is missing? __ N.

(type NUMBER only)

Tags

NGSS.MS-PS2-1