Force and Motion

Friction can be described as a:

• non-contact force
• contact force
• slowing of motion
• rough surface

Choose the BEST example of balanced forces.

• a car speeding up
• a leaf blowing in the wind
• a car moving at a constant speed
• a tennis ball bouncing back and forth between players.

Choose the BEST answer that describes how the mass of an object affects its motion.

• The greater the mass of an object, the slower the motion of the object.
• The greater the mass of an object, the faster the motion of the object.
• The greater the mass of an object, the greater the force to move the object.
• The greater the mass of an object, the greater the distance the object will travel.

Melissa and Gabe were testing the flight of leaves as they tossed them in the air.  The leaves would go up and then came to a rest on the ground.  What force made the leaves land on the ground?

• gravity
• friction
• air pressure
• mass

The 5th graders were playing a game of tug-of-war.  The class was divided equally with half the class on one side of the rope and the other half on the opposite side.  For 5 minutes the students pulled and pulled but neither side could pull the flag to one side or the other.  Choose the description of the forces during the 5th grade tug-of-war.

• The forces were unbalanced in the game.
• The forces were friction, gravity, and chemical energy.
• The students all had the same amount of strength.
• The forces were balanced in the game.

What can cause a moving object to increase its speed in a forward direction?

• a force pushing on the object from the opposite direction

• force that moves continuously in the same direction as object

• an increase in the mass of the object

A pencil falls off of a desk. What moves the pencil toward the floor?

• mass

• friction

• gravity

• speed

4 cars are at the starting line of a race. Which car will require the most force to start moving?

• car with mass of 1200 kilograms

• car with mass of 1500 kilograms

• car with mass of 1700 kilograms

• car with mass of 2000 kilograms

Which will most likely stop an object in motion?

• mass

• acceleration

• force

Which is the force that pulls a ball to the ground after being dropped?

• friction

• air resistance

• gravity