Terms
What is the study of the cause for the change in motion?
Dynamics
Into what two components can a projectile's motion be resolved?
horizontal and vertical
What is Newton's first law of motion?
Every body continues in its state of rest unless an outside force acts upon it.
What is Kepler's second law of motion?
A planet sweeps out equal areas in equal intervals of time as it orbits the sun.
A car stops completely, then accelerates to 50 km/h in 12 seconds. What is the acceleration is meters per second squared?
a=vxt=50000/3600x12=1.16 m/sec2
Greek beliefs were based on what?
human reasoning
A projectile follows a path called a _______________.
Parabola
What is Newton's second law of motion
Acceleration is directly proportional to the resultant force and inversely proportional to the mass.
This formula describes which law?
F=G x m1 x m2/r2
The law of universal gravitation
A swimmer jumps from a cliff and enters the water 2.00 seconds later. How high is the cliff?
s=1/2gt2=19.6 m
Name the three divisions of mechanics
dynamics, kinetics, statics
Acceleration and ___________ are two factors that are directly related.
force
What is Newton's third law of motion?
When any two bodies interact, the force exerted by the first is equal and opposite to the second force.
Who proved that planets travel in elliptical orbits?
Kepler
A body falls for 4 seconds. What is its average velocity?
V=1/2Vf
Vf=gxt
1/2(9.81)(4)=19.6 m/sec
What is a vector that has both speed and direction?
Velocity
Acceleration and ____________ are two factors that are inversely related.
mass
What is Kepler's first law of motion?
Each planet moves about the sun in an elliptical orbit; the sun is at one focus of the ellipse.
Why is Kepler's third law of planetary motion so helpful to astronomers?
They can calculate the distance of the planets from the sun.
A bullet is fired at a 10 degree angle at a velocity of 150 m/sec. What is its max height?
mh=1/2Vv x Vv/g=34.6 m
What are the three quantities that can be calculated when the velocity and angle are known?
Max height, range, time of flight
Gravity between two objects is directly proportional to the product of _______________ and inversely proportional to the square of the _______________.
mass, distance
What is Kepler's third law of motion?
The square of a planet's period is directly proportional to the cube of its distance from the sun.
What happens to the velocity of a planet when it orbits closer to the sun?
it increases
A bullet is fired at a 30 degree angle with a velocity of 200 m/sec. What is the range of the bullet?
range=v x ft=3,533 m