Physics S1 Review

A rocket increases its speed from 10 m/s to 82 m/s in 9.0 s. What is its acceleration?

• 8.0m/s/s

• 9.0m/s/s

• 10m/s/s

• 82m/s/s

The diagram represents the relationship between velocity and time of travel for four cars (A, B, C, and D) in straight-line motion.  Which car has the greatest acceleration during the time interval 10 seconds to 15 seconds?

• Line A

• Line B

• Line C

• Line D

Several students in a physics class recorded measurements in the table below. Which student recorded a vector measurement? [1b3]

AJ 45 kg

Bailey 75 m, north

Cloe 2 m/s

Debbie 5 minutes

• AJ

• Bailey

• Cloe

• Debbie

Two students are debating on what happens when two objects are dropped.  Student 1 stated that all objects fall at the same rate due to Earth’s pull, but that objects like feathers fall slower due to air resistance.  Student 2 also stated that all objects fall at the same rate, but that objects like feathers fall slower because they are lighter.  Which student is correct in their understanding of falling objects?

• Student 1

• Student 2

• Both students

• Neither student

A stunt coordinator has been tasked with designing a stunt where a chase car drives off of a cliff and lands on a gas station that is 100 m away from the cliff. He must make sure that the stunt car lands at exactly the correct spot so that the safety nets, cameras, and explosives all work. After some thinking, the stunt coordinator records the following measurements:

Height of the cliff 30 m

Speed of the car when leaving the cliff 40 m/s

Mass of the car 500 kg

Has the stunt coordinator collected all of the measurements he needs in order to know if the car will hit its target?

• Yes he only needs the height of the cliff and mass of the car

• Yes he only needs the height of the cliff and speed of the car

• Yes he only needs the speed of the car and the mass of the car

• No he needs to collect more data

 In the absence of air resistance, does the horizontal velocity (vx) of a projectile change as it moves along its trajectory?

• Only for projectiles rolling off a table

• It always changes

• It never changes

• Only for projectiles launched from a cannon

A projectile is launched horizontally with an initial speed of 57 m/s. What are the horizontal and vertical components of its velocity 3.0 s after it is launched?

• Vx= 47.2m/s, Vy=-47.2m/s

• Vx=57m/s, Vy=-29.4m/s

• Vx=47.2m/s, Vy=-9.8m/s

• Vx=57m/s, Vy=-9.8m/s

After a marble launched straight up vertically reaches the top of its path and begins to fall back down. What is its acceleration (neglecting air resistance)?

• Greater than when it was at the top of its path

• The same as when it was at the top of its path

• Less than when it was at the top of its path

• Not enough information to determine

A car accelerates at 3 m/s 2. Assuming the car starts from rest, how much time does it need to accelerate to a speed of 30 m/s?

• 2 seconds

• 10 seconds

• 60 seconds

• 80 seconds

If the net force on an object is zero, what would be its acceleration?

• Less than zero

• Exactly zero

• Greater than zero

• Depends on the situation