Newton's Laws of Motion

This rock, known as Balanced Rock, sits on a thin pedestal of rock in a canyon in Idaho. Balanced Rock exerts (1)____________force on the pedestal. At the same time, the pedestal exerts (2)_________________ force that is equal in size and opposite in direction. That is why Balanced Rock is stable!

• 1. a downward

• 1. an upward

• 2. a downward

• 2. an upward

Which statements describe the motion of Balanced Rock relative to different reference points?

• The rock is at rest no matter which reference point is used.

• The rock is accelerating compared to the sun.

• The rock is not accelerating compared to the sun.

• The rock has a constant velocity relative to the moon.

Imagine that the truck is acted on by an unbalanced force from the thrust of the air exiting the balloon. From the reference point of the truck, the balloon (1)______________moving. The balloon (2)______________moving from the reference point of the tape on the ground.

• 1. is

• 1. is not

• 2. is

• 2. is not

As the balloon pushes air backward, Newton’s___________law of motion states that the air will push the balloon forward. The balloon is attached to the truck, so the force on the balloon will also be applied to the truck.

• first

• second

• third

Newton’s ____________ law of motion states that this __________ force on the truck will cause the truck to move forward.

• first

• second

• third

• balanced

• unbalanced

Finally, Newton’s____________law of motion says that the acceleration of the truck will be proportional to the unbalanced force on the truck.

• first

• second

• third

Given the position of an object at two different times, which of the following can you determine?

• the average speed of the object over the given time

• the average velocity of the object over the given time

• the average acceleration of the object over the given time

Speed is the rate of distance traveled per unit of time. Velocity includes both ___________ and direction.

• velocity

• speed

• acceleration

____________ is the rate of change of velocity.

• Velocity

• Speed

• Acceleration

Which of the following statements about inertia and Newton’s first law of motion are true? Select all that apply.

• Inertia is the tendency of an object to resist a change in motion.

• Inertia is related to mass.

• An object with balanced forces will not move.

• Newton’s first law of motion is sometimes called the law of inertia.

• Newton’s first law of motion states that acceleration of a mass is proportional to the force acting on the mass.