Vocab
What is force?
a push or pull interaction upon an object
A roller coaster car rapidly picks up speed as it rolls down a slope. As it starts down the slope, its speed is 4 m/s. But 3 seconds later, at the bottom of the slope, its speed is 22 m/s. What is its average acceleration?
6 m/s^2
What do you do when two vectors point in the SAME direction?
add
Does a speedometer of a car read average speed or instantaneous speed? How?
Instantaneous speed, measures speed at a instant of time
Displacement
an object's overall change in position
What is speed?
how fast something is
A cyclist accelerates from 0 m/s to 8 m/s in 3 seconds. What is his acceleration? Is this acceleration higher than that of a car which accelerates from 0 to 30 m/s is 8 seconds.
3.8 m/s^2, no
What do you do when two vectors point in the OPPOSITE, or AGAINST each other?
subtract
If a speedometer of a car reads 40km/hr, can you say 100% for sure that the car has a constant velocity?
No, the driver can manipulate speed
When two object fall at same time at the same height, without air resistance, which hits the ground first?
both fall at the same time
What is acceleration?
rate at which velocity changes with time
A physics book is moved once around the perimeter of a table of dimensions 1.0m by 2.0m. If the book ends up in its initial position, what is its displacement?
0 m or returning position
What is scalar?
a measurement that only takes magnitude into account?
What two controls on a car can cause a change in speed?
gas and brake pedals
Inertia
the resistance of any physical object to a change in its velocity (motion after action upon object)
What is free fall?
a falling object that's only affected by gravity. NO air resistance.
You and your friend each drive 50 km. You travel 90 km/h. Your friend travels at 95 km/hr. How long will your friend be waiting for you at the end of the trip?
3 min
What is vector?
magnitude and direction in account
What control causes a change in velocity?
steering wheel
With an average acceleration uniformly from rest to 6.6 m/s in 6.5 seconds. Find the distance the car traveled during this time.
27 sec
What is projectile motion?
the motion of an object thrown or projected into the air, subject to only the acceleration of gravity
A car drives for 2.0 hrs at 40 km/hr, then for 2 hrs at 60 km/h. What is the average velocity?
50 km/hr
When two vectors are perpendicular, you must use what?
pythagorean theorem
What is acceleration of a car that travels in a straight line at a constant speed?
0 m/s^2
Mrs. Norton's crazy dog, Daisy, accelerates towards a squirrel from 3 m/s to 10 m/s in 4 seconds. What is Daisy's acceleration?
1.8 m/s^2