Forces Pre-Assessment

An astronaut is free-floating in space near a space station and is not tethered to anything. She has some tools and a fire extinguisher. Which action would propel the astronaut back toward the space station? Select all that apply.

• She could spray the fire extinguisher in the opposite direction of the space station.

• She could throw a tool in the opposite direction of the space station.

• She could throw a tool toward the space station.

• She could roll toward the space station.

In science, force refers to . . .

• A. a moving object

• B. the way objects interact

• C. a push or pull on an object

• D. a description of an objects movement

The net force on an object that is at rest . . .

• A. is always balanced

• B. changes depending on the location of the object

• C. is the result of unbalanced forces acting on the object

• D. depends on the balanced forces acting on the object

Look at the picture of the book lying on the table. Which object(s) are exerting forces and in which direction(s)? Why doesn't the book fall through the table? Explain in terms of forces.

Explain how a rocket moves off the Earth's surface in terms of forces.

Gravity on Earth exerts the same amount of force on all objects. If a 4.5 kg bowling ball and a 0.45 kg basketball are dropped from the same height at the same time, the bowling ball will have a greater impact when it hits the Earth. Why?

If an astronaut floating in space is holding a tool and lets go of the tool, in which direction will the tool move?

• A. Up

• B. Down

• C. Toward the astronaut

• D. Away from the astronaut

If an astronaut floating in space is holding a tool and throws the tool, in which direction will the tool move?

• A. In the direction it was thrown, forever.

• B. In the direction it was thrown, until it falls to the ground.

• C. In the direction it was thrown, until it hits another object.

• D. In the direction opposite it was thrown.

Choose the image below that shows which person would need to use more force to pull the wagon.

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