Acceleration and the Importance of Slope

When an object falls under the influence of gravity alone. During each second of fall, the object gains a speed of ~ 10 m/s. 

• Yes

• The object is falling in water
• The object is falling on the moon
• The object is falling on Mars

The slope of the velocity-time graph is the average acceleration

• True
• False
• Depends on the graph
• Not enough information

When the velocity in the positive direction is increasing, the

• acceleration is positive like a

• no acceleration

When the velocity is constant, there is

• no acceleration b

• acceleration is positive

When the velocity in the positive direction is decreasing, the

• • acceleration is negative, as at C.

• • no acceleration, as at B.

Acceleration is the rate at which velocity changes over time.

• Acceleration is the rate at which velocity changes over time
• Acceleration is the rate at which speed changes over time
• Acceleration is the rate at which distance changes over time
• Acceleration is the rate at which time changes over velocity

• An object accelerates if its speed, direction, or both change.

• Only speed needs to change for acceleration
• Only direction needs to change for acceleration
• Both speed and direction need to change for acceleration
• Either speed or direction or both need to change for acceleration

• Acceleration has direction and magnitude. Thus, acceleration is a vector quantity.

• Acceleration is a scalar quantity
• Acceleration is a vector quantity
• Acceleration is neither scalar nor vector
• Acceleration is both scalar and vector

Position vs. Time Graph: 

• • y = position (meters)

  • x = time (seconds)

• • Slope = Velocity = Δx / t

Velocity is defined as the change in position divided by the change in time.  

• True
• False
• Depends on the situation
• None of the above