S8P3a- Speed, Velocity, Acceleration

Cars are safety tested to see how quickly they come to a stop under many conditions. The distance and time of one of these tests is graphed.

What is the change in velocity during the first second?

• 20 m/s

• 30 m/s

• 0 m/s

• 50 m/s

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

NGSS.MS-PS3-1

Which car is accelerating?

• a car that is unmoving

• a car that rounds a curve at a constant speed

• a car that travels in straight line at a constant speed

• a car that is set to a constant speed of 60 miles per hour

Tags

NGSS.MS-PS2-2

Tommy was walking at a rate of 4 miles/hour at noon and at 12:30 pm he was walking at a brisk rate of 6 miles/hour. Two hours later Tommy was walking at a leisurely rate of 2 miles/hour. Which statement about Tommy's acceleration is true?

• Tommy had an acceleration of zero the entire time.

• Tommy had a positive acceleration between noon and 12:30 pm.

• Tommy had a positive acceleration between 12:30 and 2:30 pm.

• Tommy had a negative acceleration between noon and 12:30 pm.

John and Caroline go out for a walk one day. This graph represents their distance from home.

Which statement accurately describes their walk?

• They walked quickly, then they were still, then they walked slowly.

• They walked forward fast, then they were still, then they walked backward slow.

• They walked in one direction, then they were still, then they walked in the opposite direction.

• They walked faster and faster until they walked at a constant rate, then they walked slower and slower.

The graph represents the acceleration of two cars, Accel 1 and Accel 2, during a road trip. Which statement BEST describes the differences between the two cars' acceleration during the trip?

• Accel 1 accelerates throughout the entire trip; Accel 2 does not accelerate during the trip.

• Accel 1 rapidly accelerates and then stops; Accel 2 maintains a constant velocity during the trip.

• Accel 1 has a constant rate of acceleration; Accel 2 accelerates at different rates during the trip.

• Accel 1 accelerates for the first two-thirds of the trip; Accel 2 has a constant rate of acceleration.

Tags

NGSS.MS-PS3-1

Which point(s) on the graph indicate a change in acceleration?

• B only

• B and D

• A, C, and E

• A and E

When time was at 0 seconds, this graph describes the motion of a car that was going 10 meters per second. How fast is the car likely going after time passes?

• 0 meters per second.

• 5 meters per second.

• 10 meters per second.

• 15 meters per second.

Consider the acceleration graph. If the mass of the object that is accelerating does not change, but the force applied is tripled, how would the slope of the line change?

• The slope of the line would be zero.

• The slope of the line would increase.

• The slope of the line would decrease.

• The slope of the line would remain constant.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

At the county fair, Carrie and Sam climbed up on the carousel horses. Around and around they went; the horses also bobbed up and down. When they got off of the carousel, Carrie told Sam they had been accelerating during their ride. Sam disagreed; they had been moving at a constant speed. Whose response is fully correct, and why?

• Carrie is, because the carousel changed speed when it started and stopped.

• Sam is, because the horses never moved from their position on the carousel.

• Carrie is, because velocity includes speed plus direction, and both changed.

• Sam is, they did not accelerate since their speed remained constant for the ride.

During summer break, Jamie's family went camping in the mountains. There were no roads to their camp, 8 miles away, and it took them about 4.5 hours to reach the campsite on foot. Did Jamie's family stop to rest during the trip? How can you tell from the data?

• No. They continued moving but their speed varied.

• Yes. After 1.5 hours, there is no change in position for 30 minutes.

• No. They continued moving, although they also slowed down continuously during the trip.

• Not really. They did stop, but that was only when they reached the campsite at distance equals 0.