Chapter 2 - Linear Kinematics Part 2 (Week 2)

Question 1

What is uniform acceleration?

Answer 1

Net external force acting on an object is constant and unchanging

Question 2

What is projectile motion?

Answer 2

Motion of an object that is projected into the air or dropped and is acted on only by gravity and air resistance forces

Question 3

What are the properties of vertical motion?

Answer 3

• ignores air resistance (too small)
• Gravity is a constant force acting on the projectile
• Is a uniform acceleration (constant and unchanging)

Question 4

What is instantaneous vertical motion?

Answer 4

Vertical position at a specific time interval

Question 5

What is the difference between velocity and displacement?

Answer 5

Displacement: The change in position of an object from its starting point to its final point

Velocity: The rate of change of displacement with respect to time

Question 6

What is the equation of vertical position of a projectile?

Answer 6

yf = yi + viΔt + 1/2g(Δt)^2

Question 7

What is the equation of vertical velocity of a projectile?

Answer 7

yf = yi + viΔt +1/2g(Δt)^2

Question 8

What is the equation of vertical position of a falling object?

Answer 8

yf = 1/2g(Δt)^2

Question 9

What is the equation of vertical velocity of a falling object?

Answer 9

vf = gΔt
vf^2 = 2gΔy

Question 10

What is the equation of dropping a ball?

Answer 10

vf = gΔt
yf = 1/2g (Δt)^2

Question 11

What is the property of horizontal motion?

Answer 11

*ignore air resistance (too small)
- horizontal motion is in a straight line
- Horizontal velocity of projectile is contant

-Horizonal acceleration is always or usually zero (becuase velocity isn’t changing)

Question 12

What is the average velocity formula?

Answer 12

v =Δx/Δt

Question 13

v =Δx/Δt Using this equation, how would you find displaement?

Answer 13

Δx = (v) x (Δt)

Question 14

In a unifrom motion, is horizontal acceleration of a projectile 0 or no?

Answer 14

Yes (in a uniform motion)

Question 15

What is the equation of horizontal position of a projectile?

Answer 15

xf = xi + vΔt

Question 16

What is the equation of horizontal position of a projectio,e if the initial position is zero?

Answer 16

x = vΔt

No initial position or final position

Question 17

What must be true in a projectile in sport in terms of motion an object experiences?

Think about speed and acceleration.

Answer 17

Object contantly accelerates downaward, won’t slow down or speed up horizontally

Question 18

What value is the vertical velocity constantly changing at?

Answer 18

9.81 m/s^2

Question 19

What does time of flight depend on?

Answer 19

Depends on initial vertical velocity (vi) and initial vertical position (xi)

Question 20

What does peak of height depend on?

Answer 20

Depends on the initial vertical velocity (vi) and the initial vertical position (xi)

Question 21

What does horizontal displacement depend on?

Answer 21

Depends on initial horizontal velcoity, initial vertical velocity, and initial height

Question 22

How do you maximize flight time or peak height?

Answer 22

Maximize vertical component of release velocity

• Projection angle greater than 45 degrees

Question 23

How do you minimize flight time?

Answer 23

• Minimize the vertical component of release velocity (downward?)
• Projection angle much less than 45 degrees

Question 24

How do you maximize horizontal displacement?

Answer 24

• Maximize release velocity
• Higher release height
• Horizontal component of release velocity slightly faster than vertical