Problems Velocity &
Acceleration
Physical Science
1. A car’s velocity changes from 0 m/sec to
30 m/sec 10 seconds later. Calculate the
car’s average acceleration.
a = velocity final – velocity initial
time
a= 30 m/sec - 0 m/sec
10 seconds
a = 3 m/sec2
2. A roller coaster starts down a hill at 10
m/sec. Three seconds later, speed
increased to 32 m/sec. What is the
acceleration?
a = velocity final – velocity initial
time
a = 32m/sec – 0 m/sec
3 sec
a = 10.7 m/2
3. A swimmer speeds up from 1.1 m/sec to
1.3 m/sec during the last 20 seconds. What
was the acceleration?
a = velocity final – velocity initial
time
a= 1.3 m/sec – 1.1 m/sec
20 sec
a = 0.01 m/sec2
4. A satellite has an initial velocity of 10,000
m/sec. After a minute it is 5000 m/sec.
What is the satellite’s acceleration?
a = velocity final – velocity initial
time
a = 5000 m/sec – 10,000 m/sec
60 sec
a = - 83.3 m/sec2
Speed and Acc Ch 3 # 1 A car traveled
1025 km from El Paso to Dallas in 13.5 hrs.
What was the average velocity?
Vave = distance
time
Vave = 1025 km
13.5 hrs
Vave = 75.9 km/hour
2. A car traveling north with a velocity of 30 m/sec
slows down to a velocity of 10 m/s within 10
seconds. What is the car’s acceleration?
a = velocity final – velocity initial
time
a = 10 m/sec – 30 m/sec
10 sec
= -20 m/sec
10 sec
a = -2 m/sec/sec or 2 m/sec2
3. If the average speed of a car is 45 km/hr,
how far can it travel in 40 min?
Vave = distance
time
distance = Vave X time
distance = 45 km/hr X 40/60 minute
distance = 30 km
4. Falling objects drop with an average acc of 9.8
m/sec/sec. If an object falls from a tall building,
how long will it take before it reaches a speed of
49 m/sec?
a = velocity final – velocity initial
time
time = velocity final – velocity initial
a
time = 49 m/sec – 0 m/sec
9.8 m/sec2
Time = 5 seconds