Science 6 RR3rd

Which of the following best describes friction? It is a force that occurs ___________.

• a. between solids
• b. only on rough surfaces
• c. between solids and liquids
• d. when surfaces touch each other

Where is the gravitational force directed when you are holding a glass?

• a. away from the glass
• b. downward
• c. into the glass
• d. upward

Which of the following shows presence of friction?

• a. cars continuously roll down hills
• b. things fall off on smooth surfaces
• c. people stay in place as they move
• d. cars stop when the driver steps on the brakes

How distance between two objects affects the pull of gravity? The _________________

• a. lesser the distance, the lesser the gravitational pull between them
• b. greater the distance, the lesser the gravitational pull between them
• c. greater the distance, the greater the gravitational pull between them
• d. gravitational pull between them depends on their weights

Why does a car travel faster in going down than in going up? It is ____________________.

• a. pushed by the wind
• b. moving against gravity
• c. moving toward gravity
• d. pulled the weight on the car

Which of the following statement is NOT true? Gravity__________________.

• a. draws objects towards the center of the earth
• c. determines your weight here on earth
• c. pushes an object upward
• d. pulls object downward

Which shows that sometimes friction is undesirable?

• a. pushing furniture
• b. lighting a matchstick
• c. walking on wet floors
• d. using the brakes when approaching a stoplight

For objects here on earth, the gravitational force on them is always__________ while the frictional force is always?

• a. downward; sideward
• b. upward; sideward
• c. downward; opposite its motion or impending motion
• d. upward; opposite its motion or impending motion

For a car parked on an inclined street, the gravitational force on it is directed _________________.

• a. upward
• b. downward
• c. downward along the street
• d. upward along the street

While you stand on the floor, Earth exerts a _____________ force on you, directed _____________.

• a. frictional; sideward
• b. frictional; downward
• c. gravitational; upward
• d. gravitational; downward