Physics 3.3 &3.4
A batter hits a pop fly straight up. (a) Is the acceleration of the ball on the way up different from its acceleration down? (b) Is the acceleration of the ball at on the way the top of its flight different from its acceleration just before it lands?
A) no B) no
How far does a freely falling apple drop in 5.0 s after being released from rest?
120 m
What does it mean to say an object is in free fall
Only gravity influence
Standing at the edge of a cliff, you drop ball 1 from rest. Later you throw ball 2 downward with a certain initial speed. When the balls reach the base the cliff, is the increase in speed of ball 1 greater than, less than, or equal to the increase in speed of ball 2? Explain.
Greater than becuase the increase in speed slows down as the ball is dropped
What does the intercept of the position time graph represent? What does the initial slope represent?
Initial position and velocity
If the speed of a vehicle doubles, how does this affect the time required for it to stop?
It's doubled
An object is dropped at t = O and allowed to fall freely toward the ground. Is the distance = 0 and t = 1s greater covered by the object betweent than, less than, or equal to the distance covered by the object between t 1s andt = 2 s?
Less than
The position-time graph for an object moving with constant acceleration starts off with a positive slope. At later times the slope becomes negative. Is the initial velocity of this object positive, negative, or zero? Is the acceleration positive, negative, or zero?
Positve/ negative
An object moves with a constant acceleration. What is shape of its velocity time graph
Straight line
Why are the units of acceleration meters per second squared?
The change in velocity is m/s/s
Can an object that is moving upward be in free fall?
Yes
If the velocity of a ball is positive, can it's acceleration be negative?
Yes because a marker going up had positive velocity and negative acceleration (opposite signs)
If the velocity of a ball is zero at a given instant of time, can it's acceleration at that instant be positive?
Yes because when you through a marker up and it stops at the top it is still accelerating because pull of gravity
Is it possible to round a corner with constant speed? Constant velocity?
Yes speed because it's a scalar but no velocity because it's a vector
What is the acceleration of an object whose position time graph is a straight line
Zero acceleration
An object has a position time graph that is a straight line with a negative slope. Is the acceleration negative, positive or zero
Zero bc position time with a curve is velocity
The position-time graph for an object moving with constant acceleration starts off with zero slope. At later times the slope is positive. Is the initial velocity of this object positive, negative, or zero? Is the acceleration of the object positive, negative, or zero?
Zero/positive
