Unit 4 test review

A frog leaping upward off the lily pad is pulled down by gravity and lands on another lily pad instead of continuing in a straight line.

• Newton's 1st Law of Motion (Inertia)

• Newton's 2nd Law of Motion F=ma

• Newton's 3rd Law of Motion (Action/Reaction)

Answer explanation

According to Newton's 1st Law of Motion (Inertia), an object in motion stays in motion unless acted upon by an external force. The frog's upward leap is interrupted by gravity, causing it to land on another lily pad.

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-4

When you are riding in a car and the car suddenly stops, your body continues to go forward.

• Newton's 1st Law

• Newton's 2nd Law

• Newton's 3rd Law

Answer explanation

Newton's 1st Law states that an object in motion stays in motion unless acted upon by an external force. When the car stops, your body continues forward due to inertia, illustrating this law.

Which law of motion is also known as the Law of Inertia?

• First Law

• Second Law

• Third Law

Answer explanation

The First Law of Motion, also known as the Law of Inertia, states that an object at rest stays at rest, and an object in motion stays in motion unless acted upon by a net external force.

Newton's First Law says that an object that is moving will _____.

• stay at rest

• keep moving with a constant velocity

• resist any physical change

• has mass

Answer explanation

Newton's First Law states that an object in motion will continue to move at a constant velocity unless acted upon by an external force. Therefore, the correct answer is that it will keep moving with a constant velocity.

An object in motion tends to stay in motion unless an ___ force acts on it.

• unbalanced

• balanced

Answer explanation

The correct answer is 'unbalanced' because an object in motion will continue moving at a constant velocity unless an unbalanced force, such as friction or gravity, acts on it, changing its state of motion.

Tags

NGSS.MS-PS2-2

Because of inertia, a moving object will keep ________ unless acted on by an unbalanced force.

• at rest

• moving

• in one spot

• inertia

Answer explanation

According to Newton's first law, an object's inertia will cause it to remain in motion at a constant velocity unless acted upon by an unbalanced force. Therefore, the correct answer is 'moving' because it would require an unbalanced force to stop the object.

Tags

NGSS.HS-PS2-2

You and your dad are moving the couch from one side to another. Your dad pushes with a force of 35 N to the right and you push with a force of 25 N right. What is the net force on the couch?

• 60 N right

• 10 N left

• 60 n right

• 50 N left

Answer explanation

To find the net force, add the forces together: 35 N (dad) + 25 N (you) = 60 N to the right. Therefore, the net force on the couch is 60 N right.

Tags

NGSS.MS-PS2-2

A wheeled cart is moving to the right at a constant speed.  Two forces of equal magnitude are acting upon the cart. Which of the following best describes the forces and motion of the cart?

• Balanced Forces, Constant Speed

• Balanced Forces, Acceleration

• Unbalanced Forces, Constant Speed

• Unbalanced Forces, Acceleration

Answer explanation

The cart is moving at a constant speed, indicating that the forces acting on it are balanced. Since the two forces are of equal magnitude and opposite direction, they cancel each other out, resulting in no acceleration.

Tags

NGSS.MS-PS2-2

What is the net force?

• 40 N left

• 0 N Balalnced

• 400 N right

• 40 N right

Answer explanation

The net force is determined by the direction and magnitude of the forces acting on an object. In this case, a net force of 40 N to the right indicates that the rightward forces exceed any opposing forces, confirming the correct answer.

Tags

NGSS.MS-PS2-2

What is the net force?

• 400 N Up

• 400 N Down

• - 400 N Down

• 800 N Down

Answer explanation

The net force is determined by the direction and magnitude of forces acting on an object. In this case, the net force is 400 N directed downwards, making '400 N Down' the correct choice.

Tags

NGSS.MS-PS2-2