Physics H 06 2D Motion / Gravity

A ___ is influenced only by the force of gravity

• Book on a table

• Projectile

• Tetherball on a tether

• Car turning in a circle

What is the force on a 1.0 kg mass moved in a circular motion horizontally with a radius of 1 m with a speed of 2.0 m/s? (F_r=mv²/r)

• 1 N

• 2 N

• 4 N

• 8 N

Kepler’s 3rd Law of planetary motion states that the ratio of ___

• a the orbital periods of any two planets equals the ratio of the orbital radii

• all planets would orbit with the same orbital period

• the orbital period to the orbital radius is the same for all planets

• the period squared to the radius cubed is the same ratio for all planets

What is the average speed of a rider on a carousel ride that makes a complete revolution around the circle (diameter = 20.0 m) in 10.0 seconds? (v=2 x pi x r) / T

• 3.14 m/s

• 6.28 m/s

• 31.42 m/s

• 62.84 m/s

A bowling ball is dropped from a 100m high cliff at the same time another bowing ball is launched on the same cliff horizontally at 20m/s. Which bowling ball will hit the ground first? (ignore air resistance)

• The one dropped from the cliff

• The one launched horizontally from the cliff

• Both arrive at the same time

• Not enough information is given

A bowling ball is dropped from a 100m high cliff at the same time a baseball is launched on the same cliff horizontally at 20m/s. Which ball will hit the ground first? (ignore air resistance)

• The bowling ball (it has more mass)

• The baseball (its moving faster horizontally)

• Both arrive at the same time

• Not enough information is given

A bowling ball is dropped from a 100m high cliff at the same time another bowing ball is launched on the same cliff horizontally at 20m/s. Which bowling ball will land farther away from the cliff? (ignore air resistance)

• The one dropped from the cliff

• The one launched horizontally from the cliff

• Both arrive at the same time

• Not enough information is given

A baseball is dropped from a 180m high cliff. How many seconds does it take to hit the ground? t = sqrt(2 x height)/g) ; g=10m/s²

• 2

• 4

• 6

• 8

A baseball is dropped from a 100m high cliff. It takes 4.5 s to reach the ground. How fast is it going when it hits the ground? (v_f=v₀+at ; a=10m/s²)

• 2.3 m/s

• 4.5 m/s

• 23 m/s

• 45 m/s

A baseball launcher launches a baseball straight up at 10 m/s. When it reaches the launcher again, how fast will it be moving?

• Less that -10 m/s2

• -10 m/s

• More than -10 m/s

• The baseball will reach escape velocity and never return.