Forces

Which of the following factors does NOT affect air resistance?

• speed
• spin
• size
• shape

Momentum describes

• How much force is needed to change an object's motion
• How much velocity changes in a given amount of time
• The tendency of an object to resist a change in motion
• The balanced forces on a falling object with a constant speed

Carl and Juan are playing catch. Carl throws a fastball to Juan and it hurts Juan's hand. Why is this the case?

• Greater the acceleration, greater the force
• Greater the mass, greater the acceleration
• Greater the acceleration, the less the force
• Greater the mass, the less the force

Consider a watermelon that starts from rest and drops straight down from a tall building. Air resistance can be ignored. Which statement about the watermelon's motion is FALSE?

• The watermelon falls at a constant velocity
• The watermelon has a positive acceleration
• The watermelon's acceleration due to gravity is 9.8 m/s/s
• The watermelon speeds up as it falls

What is the weight (in Newtons) of a person with a mass of 95 kg?

• 9.7 N
• 95 N
• 104.8 N
• 931 N

An object has 16 N of force being applied to the right, 16 N of force being applied to the left, and 4 N of force being applied downward. What is the net force on the object?

• 36 N
• 4 N downward
• 32 N
• 16 N to the left

A 700 kg car is driving with an acceleration of 5 m/s/s down the interstate. What is the force required to accelerate the car?

• 3,500 N
• 650 N
• 14 N
• 0.071 N

Balanced forces

• cause an object to have no motion
• cause no net change in the motion of an object
• cause an object to have a change in its motion
• act on different objects in different directions

Unbalanced forces

• always cause an object to have no motion
• cause no net change in the motion of an object
• cause an object to have a change in its motion
• act on the same object in different directions

As the distance between two objects increases, the gravitational force ____.

• increases
• decreases
• stays the same