Mistar 6.4 Forces

Forces acting on an object are balanced when:

• They are unequal in magnitude and similar in direction.

• They agree with me.

• They are equal in magnitude and opposite in direction.

• They are normal.

Tags

NGSS.HS-PS2-1

A bowling ball is rolled at the same bowling pin, at different times. The first roll moves the pin 50cm and the second roll moves the pin 100cm. This means that the second roll must have applied more force to the bowling pin than the first roll. Which of the following could describe why the second roll applied more force?

• The ball in the second roll could have had more mass than the ball in the first roll.

• The ball in the second roll could have been moving faster than the ball in the first roll at the time of the collision.

• Both 1 and 2

• Neither 1 or 2

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

To test the new helmet design, it was dropped from a height of three meters onto a hard floor. The helmet bounces off the floor, but is undamaged. Which statement correctly describes the forces involved in this collision at the moment of impact?

• The floor applies a force to the helmet that is equal to the force the helmet applies to the floor.

• The floor applies a force to the helmet that is less than the force the helmet applies to the floor.

• The force applies a force to a helmet that is greater than the force the helmet applies to the floor.

• There is not enough information to tell.

Tags

NGSS.MS-PS2-1

Seven students are playing tug-of-war, three students on one side and four students on the other side. A ribbon is tied tightly on the rope in the middle. How will the forces applied effect the motion of the rope and ribbon?

• The ribbon will move toward the side with three students.

• The ribbon will move toward the side with four students.

• The ribbon will not move either direction.

• There is not enough information to predict how the ribbon will move.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

You have two different size boxes, made of the same material, placed on a smooth, flat, slippery surface. The blocks are not moving when placed on the surface, but move easily when force is applied. Which block will have a greater change in motion when force is applied?

• The block with more mass.

• They will both have the same change in motion.

• The block with less mass.

• There is not enough information to tell.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

Forces acting on an object are unbalanced when:

• They are equal and in the opposite direction.

• They are not thinking right.

• They agree with me.

• They are unequal or in the same direction.

Tags

NGSS.MS-PS2-2

If a rock is dropped on a box of cucumbers and then stays in a stable position on top of the box. Which of the following describes the forces on the box of cucumbers at this time?

• There are no forces acting on the box of cucumbers.

• The only force acting on the box of cucumbers is applied by the rock.

• There are many forces acting on the box of cucumbers. These forces are balanced.

• There are many forces acting on the box of cucumbers. These forces are unbalanced.

Tags

NGSS.MS-PS2-4

NGSS.MS-PS2-5

A bowling ball is rolled at the same bowling pin, at different times. The first roll moves the pin 50cm and the second roll moves the pin 100cm. When the ball and the pins collide, are the forces on the bowling pin balanced or unbalanced?

• Both are balanced.

• Both are unbalanced.

• The first is balanced and the second is unbalanced.

• The first is unbalanced and the second is balanced.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

We know forces acting on an object are unbalanced when:

• everything is stable.

• everything is going crazy.

• there is motion.

• it is still.

Tags

NGSS.MS-PS2-2

Look at the diagram of forces acting on an object. The picture shows a push and a pull acting on a box of books sitting on the floor. What is the net force toward the right on the box?

• 0 N

• 50 N

• 100 N

• 2,500 N

Tags

NGSS.MS-PS2-2