Measuring Motion
An object's change in position relative to a reference point is known as...
Motion
Acceleration
Any action that can change the state of motion of an object is called a...
Force
Find the velocity in meters per second of a swimmer who swims 110 m toward the shore in 72 s.
v= d/t
v= (110 m)/(72 s)
v= 1.5 m/s toward shore
Natalie accelerates her skateboard along a straight path from 0 m/s to 4.0 m/s in 2.5 s. Find her average acceleration.
a = (vf - vi)/t
a = (4.0 m/s - 0 m/s)/2.5 s
a = 1.6 m/s2 along a straight path
What is the DISPLACEMENT of a person who runs the full circle of a 400 m track and returns to their starting position?
TRUE/FALSE: Acceleration can only be positive.
FALSE
A force that opposes motion between two surfaces that are in contact is called...
Friction
Find the velocity in meters per second of a baseball thrown 38 m from third base to first base in 1.7 s.
v = d/t
v = (38 m)/(1.7 s)
v= 22 m/s toward first base
A turtle swimming in a straight line toward shore has a speed of 0.5 m/s. After 4.0 s, its speed is 0.80 m/s. What is the turtle's average acceleration?
a = (vf-vi)/t
a = (0.80 m/s - 0.50 m/s)/4.0 s
a = 0.075 m/s2 toward the shore
TRUE/FALSE: Velocity can be negative.
TRUE
On an acceleration graph, the x-axis is time and the y-axis is...
Velocity
The four fundamental forces in nature are...
Gravity, Electromagnetic force, Strong Nuclear force, Weak Nuclear Force
Calculate the displacement in meters that a cyclist would travel in 5.00 h at an average velocity of 12.0 km/h to the southwest. Remember to include direction.
d = vt
d = (12.0 km/h)(5.00 h)
d = 50.0 km southwest
Find the average acceleration of a northbound subway train that slows down from 12 m/s to 9.6 m/s in 0.8 s.
a = (vf-vi)/t
a = (9.6 m/s - 12.0 m/s)/0.8 s
a = -3 m/s2 north (OR 3 m/s2 south)
You can plot a graph showing distance on the vertical axis and time on the horizontal axis. If the line is going up, then the velocity is...
Increasing
TRUE/FALSE: When calculating acceleration, you subtract initial velocity from the final velocity.
TRUE
A large dog and a small dog play tug of war. The large dog pulls both the toy and the small dog in his direction. This is an example of what kind of force?
Unbalanced force
Simpson drives his car with an average velocity of 85 km/h eastward. How long will it take him to drive 560 km on a perfectly straight highway?
t = d/v
t = (560 km)/(85 km/h)
t = 6.6 h
Mai's car accelerates at an average rate of 2.6 m/s2. How long will it take her car to speed up from 24.6 m/s to 26.8 m/s?
t = (vf-vi)/a
t = (26.8 m/s-24.6 m/s)/2.6 m/s2
t = 0.85 s
If a speed graph is a flat line, the speed is...
Constant
The acceleration that occurs in circular motion is known as...
Centripetal acceleration
Two students are pushing a box that is at rest. This is an example of what kind of friction?
Static friction
How much time does it take for a student running at an average speed of 5.00 m/s to cover a distance of 2.00 km?
2.00 km -> 2000 m
t = d/v
t = (2000 m)/(5.00 m/s)
t = 4.00 x102 s (or 6.67 min)
A cyclist travels at a constant velocity of 4.5 m/s westward and then speeds up with a steady acceleration of 2.3 m/s2. Calculate the cyclist's speed after accelerating for 5.0 s.
vf = vi + at
vf = 2.5 m/s + (2.3 m/s2 * 5.0 s)
vf = 16 m/s