Forces and Motion

If a train travels west at 80 mph for 4 hours, what distance will the train travel? (speed = distance ÷ time)

• 20 miles

• 84 miles

• 100 miles

• 320 miles

A runner traveled 6 miles in one hour. During the next hour, she traveled 8 miles. Which best describes the motion of the runner during the second hour?

• speeding up

• slowing down

• changing direction

• remaining the same

An airplane traveled 400 miles in one hour. By the end of the next hour, it had traveled a total of 800 miles. Which best describes the motion of the airplane?

• It was moving at a faster speed during the first hour.

• It was moving at a faster speed during the second hour.

• It was moving at the same average speed for the two hours.

• The airplane stopped moving between the first and second hours.

A car travels at a speed of 50 miles per hour. What distance does the car travel in two hours? (speed = distance ÷ time)

• 2 miles

• 25 miles

• 50 miles

• 100 miles

Which tools will be most helpful to a scientist measuring motion?

• a scale, a compass, and a stopwatch

• a stopwatch, a scale, and a thermometer

• a compass, a stopwatch, and a measuring tape

• a measuring tape, a stopwatch, and a thermometer

When two equal and opposite forces are at work, what happens to motion?

• It increases.

• It decreases.

• There is no motion.

• There is a maximum friction.

Which is the best example of unbalanced forces acting on an object?

• a boy sitting on a chair

• a dog holding a ball in its mouth

• a girl jumping off her skateboard

• a marble rolling at a constant speed

On which surface would a toy car travel the farthest if pushed with the same amount of force?

• ice

• grass

• carpet

• concrete

Which best represents the relationship between force and the mass of an object?

• The greater the force, the smaller the object.

• The smaller the force, the smaller the object.

• The force on an object determines what density it has.

• The greater the mass of an object, the greater the force needed to move it.

Which best explains how an object’s motion changes when additional force is applied?

• As force increases, acceleration increases.

• As force increases, acceleration decreases.

• As force increases, the object’s mass changes.

• As force increases, the object’s direction changes.