Terms
Speed plus direction.
Velocity
On a speed graph, the y-axis is labeled with?
Distance(m)
On an acceleration graph, the y-axis is labeled with?
Speed(m/s)
What is the speed of an object at rest?
0 m/s
. Which of the following is not a vector quantity? a.Speed b.Velocity c.Displacement
speed
This force opposes motion
friction
On a speed graph, the x-axis is labeled with?
Time(s)
On an acceleration graph, what does a straight horizontal line represent?
Constant speed/velocity
Suppose a car is moving in a straight line and steadily increases its speed from 35 m/s to 45 m/s in 2 seconds. What is the cars acceleration?
5 m/s2 forward
Give an example of strong nuclear force
Nuclear fusion in the core of the sun
Distance traveled divided by the time it took.
Speed
On a speed graph, what does a straight horizontal line represent?
At rest/no motion
On an acceleration graph, what is the x-axis labeled with?
Time (s)
A car rounds a corner, but keeps it's speed constant. Is it accelerating?
Yes--direction is changing and acceleration is a vector quantity
What is the unit for acceleration?
m/s2
Define displacement.
The distance between the starting and end points and the direction in which you travel
On a speed graph, the steeper the line on the graph, the___________________the motion?
Faster
How do you calculate acceleration from a velocity vs time graph?
Slope = rise/run or (y2-y1)/(x2-x1)
A car travels 100 m in 5 s. What is its average speed?
20 m/s
Name a time when you would want to increase friction--(a time when more friction is helpful)
Slippery roads, batting gloves, cleats, etc...
What is centripetal acceleration?
A special type of acceleration when speed is constant, but the object is accelerating because the direction is always changing. Constant speed in a circle.
On a distance vs. time graph, was does the slope of the line represent?
It's speed
What are 3 ways an object can accelerate?
Speed up, slow down, or change direction
A car is traveling west with a constant velocity of 20 m/s, when suddenly a deer jumps in it's path. It slams on it's brakes to a stop and decelerates quickly at -5 m/s2. How long does it take for the car to stop?
4 seconds
Which has more friction--rolling or sliding? Why?
Sliding friction because there is more surface area in contact with another surface