APC kinematics reading quiz

Mathematically, ______________is defined as:   $\lim_{t\rightarrow0}\ \frac{\Delta r}{\Delta t}$ where the direction of ∆ r is the direction of motion at a given instant. 

• distance

• displacement

• instantaneous velocity

• acceleration

The reason we can rewrite   $\lim_{t\rightarrow0}\ \frac{\Delta v}{\Delta t}$  as  $\frac{\text{d}v}{\text{d}t}$  is because this is the limit definition of a derivative.

• True

• False

The reason we can rewrite   $\lim_{t\rightarrow0}\ \frac{\Delta v}{\Delta t}$  as  $\frac{\text{d}v}{\text{d}t}$  is because this is the derivative definition to find the instantaneous velocity.

• True

• False

A body's position function is r(t) =  $[(7k_1t^3)i-(4k_2/t)j]$ meters (the k's are added for the sake of units--we will ignore them from here on--i.e., set their magnitudes at one). What is v(t)?

•  $[(21k_1t^2)i-(4k_2/t^2\ )j]$  m/s

•  $[(21k_1t^2)i+(4k_2\ln\left|t\right|\ )j]$  m/s

•  $[(21k_1t^2)i+(4k_2/t^2\ )j]$  m/s

•  $[(21k_1t^2)i+(4k_2/t^{ }\ )j]$  m/s

An airplane lands on a runway with a velocity of 150 m/s. How far will it travel until it stops if its rate of deceleration is constant at -3 m/s²?

• 525 m
• 3750 m
• 6235 m
• 9813 m

Tags

NGSS.HS-PS2-1

A ball is thrown downward from the top of a roof with a speed of 25 m/s. After 2 s, its velocity will be:

• 19.6 m/s
• -5.4 m/s
• -44.6 m/s
• 44.6 m/s

Tags

NGSS.HS-PS2-1

What happens to the velocity of a ball as it is dropped off a cliff? 

• It decreases at a uniform rate 
• It increases at a uniform rate 
• It is constant 
• It increases at a non-uniform rate

Tags

NGSS.HS-PS2-1

NGSS.HS-PS2-4

For projectiles, a_x = __________ and a_y = __________.

• 0 m/s/s and -10 m/s/s

• -10 m/s/s and 0 m/s/s

• 0 m/s/s and 0 m/s/s

• -10 m/s/s and -10 m/s/s

Tags

NGSS.HS-PS2-1

Which will hit the ground first if dropped at the same time?

• The blue ball because it doesn't have to go as far.

• The blue ball because it falls straight down.

• The green ball because gravity accelerates it.

• Both will hit the ground at the same time.

Tags

NGSS.MS-PS2-4

A box is dropped from an airplane. Neglecting air resistance, where will the box be in relation to the plane when the box hits the ground?

• directly under the plane because it has the same Vx as the plane.

• behind the plane because the box will drop straight down

• in front of the plane because the plane will throw it forward

• there is not enough information to tell