Free Fall and Kinematics

A particle's position is given by the function x(t)=(-t³+3t) where t is in seconds. What is the object's velocity at t = 2 seconds?

• -2

• 9

• -9

• 2

Fred is driving at a steady 20 m/s when he passes Betty sitting at rest in her Prius. Betty instantly begins accelerating at 5.0 m/s². How far does Betty have to drive to overtake Fred?

• 20 m

• 100 m

• 8 m

• 160 m

What is the acceleration of gravity?

• 9.8 m/s²

• 9.8 m/s

• 4.9 m/s

• 4.9 m/s²

Tags

NGSS.HS-PS2-4

If a Samsung Galaxy S9 (mass: 0.168 kg) and an iPhone X (mass: 0.846 kg) are dropped from a 50 m tower, which will hit the ground first? Assume no air resistance.

• Galaxy S9

• iPhone XS

• Tie

Tags

NGSS.HS-PS2-1

If an antelope jumps by extending its legs forcefully, accelerating at 35 m/s for 0.70 m as its legs straighten. How high does it go?

• 2.0 m

• 2.5 m

• 11 m

• 8.6 m

Tags

NGSS.HS-PS2-1

NGSS.HS-PS3-1

In which of the following situations can an object be speeding up?

• v is negative and a is positive

• v is positive and a is negative

• v is negative and a is negative

• v is positive and a is zero

Tags

NGSS.HS-PS2-1

Cleveland is 300 miles east of Chicago. A plane leaves Chicago flying due east at 500 mph. The pilot forgot to check the weather and doesn't realize the wind is blowing south at 50 mph. What is the plane's speed relative to the ground?

• 450 mph

• 502 mph

• 550 mph

• 500 mph

Tags

NGSS.HS-PS2-1

James drops his car keys from the top of a roof located 8.52 meters above the ground. How long will it take the keys to reach the ground?

• 0.89 seconds

• 2.45 seconds

• 5.43 seconds

• 1.32 seconds

Tags

NGSS.HS-PS2-1

NGSS.HS-PS2-4

If an object is thrown straight upward, what is it's speed when it reaches it's maximum height?

• Its maximum speed

• Zero

• Its initial speed

• 9.8 m/s²

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-2

A projectile is launched at an angle of 22 with an initial velocity of 15 m/s up an inclined plane that makes an angle of 10 with the horizontal. Find the time it takes for the projectile to hit the inclined plane at point M.

• 1.16 seconds

• 1.50 seconds

• 2.5 seconds

• 4.59 seconds