U3 Kinematics Review

Distance & Displacement

100

Is distance or displacement a vector?

Displacement

200

If you walk 2 feet north, 3 feet west, 3 feet south, and 3 feet east, what is your displacement?

-1 feet (or south 1 foot)

300

A flat line on a distance vs time chart means an object is what? 

Not moving.

400

The steeper the line on a distance vs time graph, the faster the ____________. 

Velocity.

500

If Sally walks 4 blocks North from her starting point then walks 3 blocks East. What is her overall displacement?

Answer: x = (a2) + (b2)

x = (42) + (32)

x = 16 + 9

x = 25

x = 5 m

Speed & Velocity

100

Is speed or velocity a vector?

Velocity

200

A speedometer is an example of __________ speed. 

Instantaneous.

300

What is the unit of measurement for velocity?

m/s

400

1. If you have a vehicle moving across a length of 150 m in 21 seconds, what is the speed of the object? 

Answer: v = x/t

v = 150/21

v = 7.14 m/s

500

If you're moving at 50 mph on a perfectly round race track, in physics are we measuring speed or velocity?

Velocity

Acceleration & Graphs

100

How do you indicate a negative acceleration?

Negative sign (or south or east direction)

200

What is the equation for calculating acceleration? 

(vf-vi)/t

300

The slope of the line on a velocity vs time graph shows what?

acceleration

400

What is the unit of measurement for acceleration? 

m/s²

500

How long will it take a car traveling 30 m/s  to come to a stop if its acceleration is 3 m/s²?

t = (vf - vi) ÷ a 

t = (0m/s-30m/s)÷(-3m/s²)

t = -30 m/s ÷ -3m/s²

t = 10 s

Projectile Motion

100

What is gravity on Earth? 

-9.8 m/s²

200

What is an abbreviation to remember sine, cosine, and tanget in reference to measuring the opposite, adjacent, or hypotenuse sides? 

Soh-Cah-Toa

300

While projectile motion refers to both the y-axis and x-axis, the two calculations must be considered __________________. 

independently.

400

1. If a projectile is launched horizontally from a height of 7 m with an initial horizontal velocity of 3.5 m/s. How much time will it take the projectile to land?

Answer: Find the time it spend in flight

y = y0*t + ½*ay*t^2 

-7 m = 0*t + ½*(-9.8)*t^2

-7 = -4.9*t^2 

1.429 = t^2

t = 1.195 s

500

If a projectile is launched horizontally from a height of 7 m with an initial horizontal velocity of 3.5 m/s. How far away will the projectile land from the edge of the table?

Now calculate the length away from the table it will fall 

vx = x/t

3.5 = x/1.195

3.5*1.195 = x 

x = 4.1825 m