Unit 4 Quiz 2 Retake

As an object travels through the air, its vertical velocity 

• changes continuously
• remains the same

What is the horizontal acceleration of a projectile? (neglect air resistance)  

• 0 m/s²
• 9.8 m/s²

Tags

NGSS.HS-PS2-1

What is the vertical acceleration of a projectile? (neglect air resistance) 

• 0 m/s²
• 9.8 m/s² down
• 9.8 m/s² up

Tags

NGSS.HS-PS2-1

NGSS.HS-PS2-4

At the top of a projectile's path above Earth, the vertical acceleration of an object is

• is zero
• goes from positive to negative
• goes from negative to positive
• remains unchanged

Tags

NGSS.HS-PS2-1

A ball is thrown horizontally from the top of a building with an initial velocity of 13m/s.  At the same time, a second ball is dropped from the top of the same building.  Which of the following is the same for the two balls?

• Their final displacement
• Their paths as they fall
• Their initial horizontal velocities
• Their final vertical velocity as they reach the ground

If you shoot a gun and at the same time drop a bullet which will hit the ground first? Why?

• The bullet that is shot, because it is going faster
• The dropped bullet, because gravity pulls on it.
• At the same time, because the x and y components are independent of each other. 
• This cannot happen

Tags

NGSS.HS-PS2-4

A cannonball is fired at a 45.0° angle and an initial velocity of 625 m/s. Assume no air resistance. What is the vertical component of the cannonball’s velocity? What is the horizontal component of the cannonball’s velocity?

• -625 m/s; 625 m/s
• 441.9 m/s; 441.9 m/s
• -441.9 m/s; 441.9 m/s
• 0 m/s; 625 m/s

Horizontal velocity is constant.

• True
• False

Tags

NGSS.HS-PS2-2

If I throw a crayon straight up at 12m/s, how fast is its speed when i catch it at the same height?

• 6 m/s
• 12 m/s
• 18 m/s
• 24 m/s

Tags

NGSS.HS-PS2-1

Does vertical velocity change as a projectile rises and falls?

• yes 
• no