Formulaic
Write out the speed formula (and what each letter means):
S = d/t
What is average speed? Give an example:
The total distance traveled divided by the total time taken
Varies
Henry bikes 10km home. He leaves school at 3 and gets home at 3:30. What is his average speed? What is his instantaneous speed at 3:15?
Average speed: 20km/h
Instantaneous speed: unknown
What two things do you need to determine velocity?
Speed and direction
The speedometer on your car says you are traveling at a constant speed of 30mph. Are you accelerating?
Write out the momentum formula (and what each letter means):
p = mv
Kylie walks 2 km north, then 2 km east, then 2 km south, then 2 km west. How far does she travel? What is her displacement?
8 km. 0 km
What are the units for these words?
Momentum
Velocity
Acceleration?
Kg*m/s n
m/s n
m/s2
What three things can occur when an object is accelerating?
Change in direction, speed up, slow down
Thinking about momentum, why is it dangerous to cross a railroad track, even if the train is far slower than you are?
The train has more mass
Write out the acceleration formula (and what each letter means):
A = f - i / t
What happens to the speed of the bowling ball when it hits the pins? The speed of the pins?
The bowling ball slows down and the pins increase speed.
A car increases its speed from 10 m/s to 30 m/s in 4 seconds. What is its acceleration?
5 m/s²
A bowling ball has a mass of 6 kg and a momentum of 42 kg·m/s. What is the velocity of the bowling ball?
252 kg*m/s
A truck has a momentum of 30,000 kg·m/s and is moving at 15 m/s. What is the mass of the truck?
2,000 kg
Write out the velocity formula (and what each letter means):
v = p/m
What is instantaneous speed? How is it different from average speed? Give an example:
Instantaneous speed is the speed at any given time. Average speed is total time divided by total distance.
Varies
A cyclist slows down from 15 m/s to 5 m/s in 5 seconds. What is the acceleration (deceleration) of the cyclist?
-2 m/s2
If a rocket accelerates at 10 m/s² and starts from rest, what will its velocity be after 8 seconds?
80 m/s
What happens to the momentum of a bowling ball when it hits the pins? Where is some of it transferred to?
The bowling ball slows somewhat, and the pins absorb that momentum
Write out the final speed formula (and what each letter means):
F = t(a) + i
A truck is moving at a constant speed of 72 km/h. After 3 hours, the truck encounters a 20-minute delay due to a traffic jam. Following the delay, the truck continues its journey at a speed of 60 km/h for the next 2 hours before reaching its destination.
How far did the truck travel in total?
336 km
A car decelerates uniformly around a curve from 50 m/s to 20 m/s in 5 seconds. After the curve, the car then accelerates again to 60 m/s in the next 10 seconds. What are the two accelerations?
1: -6m/s2
2: 4m/s2
A 1,500 kg truck is moving at a velocity of 20 m/s. It collides with a stationary car of mass 1,000 kg. After the collision, the two vehicles stick together and move as one combined mass.
If the velocity after the collision is 12 m/s, then what is the momentum of the two vehicles?
A 2 kg ball is rolling at 3 m/s toward another identical 2 kg ball that is at rest. After an elastic collision, the moving ball stops, and the stationary ball moves away. What is the momentum of each ball before and after the collision?
(elastic collision means all the momentum continues)
ball 2: 6kg*m/s
ball 1: 0