Dr. Mason’s Patented Quiz #2 Review Presentation

Accept no substitutesVoid where prohibited

Limit one per family

“Everyone fights, nobody quits”

Fill in the blanks

• V0 =

• Vi =

• Difference between V0 and Vi =

• V0X =

• V0Y = • Pythagorean Theorem = • T =

Trig Stuff

A = 13

b = 9

c =

Trig Stuff

A = 13

b =

c =

Θ = 400

Más Trig

y

x

V0 = 25 m/s

Draw V0X and V0Y to scale on graph

V0X = V0Y =

Θ = 350

Más Trig

y

x

V0 = 25 m/s

Draw V0X and V0Y to scale on graph

V0X = V0Y =

Θ = 1400

Vectors

V0X = - 60 m/s

V0Y = 35 m/s

Θ =

V0 =

VectorsV0X = - 40 m/s

V0Y = - 25 m/s Θ =

V0 =

Vector Problems• A plane flies due north at a speed of 400 km/hr• The wind blows towards the east at a speed of

100 km/ hr.• Draw a diagram depicting this. • Calculate the magnitude and direction of Vf.

Vector Problems• As previously, a plane flies at 400 km/hr with a

wind blowing east at 100 km/hr. • At what heading does the plane need to fly in

order to end up flying due north? Draw a diagram.

Projectile motion concepts

• Motion in horizontal and vertical directions are:

• Acceleration always points:• Why:• The vertical speed of a projectile at the apex

of its trajectory:

Projectile motion concepts again• The point in the trajectory where the

projectile moving the slowest:• Why:• Describe the horizontal and vertical

components of velocity at these 5 places:

Final velocity, vector style

A plane flying horizontally at a speed of 200 m/s drops a care package from a height of 1000m. Whenthe care package hits the ground, these are the magnitude and direction (measured from the positiveX-axis) of its final velocity.

Figuring out V0X and V0Y

• A projectile launches from the ground and lands 120m downrange in 3.4 seconds

• After how long did it reach its apex?• What is V0X?

• What is V0Y?

Figuring out V0X and V0Y

• A projectile launches from the ground and lands 120m downrange in 3.4 seconds

• How high did the projectile go?• What was the launch angle?• What was the original launch speed V0?

Equations for 2-D motion

• V0X (in terms of V0 and θ)=

• V0Y (in terms of V0 and θ)=

• Free fall equation (no V0Y):

• Y- Y0 (in terms of V0Y , g, t) =

The infamous boy throwing rock off the cliff problem

• A boy throws a rock horizontally off a 130m cliff. The rock’s V0 = 15 m/s.

• How long after the rock is thrown does it hit the ground? How far did it travel horizontally?

The infamous punter hang time problem

• A football punter kicks the ball with a speed of V0 = 35 m/s at an angle of 380 from the horizontal. How long does it stay in the air? How long to reach its apex?

The infamous ‘how far does the punter kick the ball’ problem…with a twist

• A football punter kicks the ball with a speed of V0 = 35 m/s at an angle of 380 from the horizontal. How far does the punter kick the ball?

• How high does it go?

The range equation• The range equation:• A cannon shoots a human at an angle of 400

and a V0 of 50 m/s. How far downrange does he land?

• Pretend air resistance is now turned on. How would that affect the range calculated in the previous problem?