Polytechnic University of Puerto Rico
PSE
Physics Tutoring
SCIE 0110 Introduction to Physics
Displacement, Velocity and Acceleration
Name _____________________________
Section _________ Term__________
Prof. _____________________________
Tutor William Vélez
Physics is an experimental science that studies phenomena of nature, and tries to find
patterns and principles that relate these phenomena.
1. What is the difference between displacement and distance?
2. What is the distinction between speed and velocity?
3. Describe a situation in which an object’s speed is constant but its velocity is not.
Polytechnic University of Puerto Rico
PSE
Physics Tutoring
SCIE 0110 Introduction to Physics
Displacement, Velocity and Acceleration
Name _____________________________
Prof. _____________________________
Section _________ Term__________
Tutor William Vélez
(2.14) The Figure below shows the velocity of a solar-powered car as a function of time. The driver
accelerates from a stop sign, cruises for 20 s at a constant speed of 60km/h, and the brakes to come to a
stop 40s after leaving the stop sign.
a) Compute the average acceleration during the following time intervals:
i. t1 = 0 s to t2=10s
ii. t1 = 30 s to t2=40s
iii. t1 =10 s to t2=30s
iv. t1 = 0 s to t2=40s
b) What is the instantaneous acceleration at t=20s and at t=35s?
Polytechnic University of Puerto Rico
PSE
Physics Tutoring
SCIE 0110 Introduction to Physics
Constant Acceleration
Name _____________________________
Section _________ Term__________
Prof. _____________________________
Tutor William Vélez
(2.4) A motorcyclist heading east through a small Iowa city accelerates after he passes the signpost marking
the city limits. His acceleration is a constant 4m/s2.At time t=0 he is 5m east of the signpost, moving east at
15m/s.
a) Find his position and velocity at time t=2s.
b) Where is the motorcyclist when his velocity is 25m/s?
Polytechnic University of Puerto Rico
PSE
Physics Tutoring
SCIE 0110 Introduction to Physics
Constant Acceleration
Name _____________________________
Prof. _____________________________
Section _________ Term__________
Tutor William Vélez
(2.5) A motorist traveling with a constant speed of 15 m/s passes a school-crossing corner, where the speed
limit is 10 m/s. Just as the motorist passes, a police officer on a motorcycle stopped at the corner starts off
in pursuits with constant acceleration of 3m/s2.
a) How much time elapses before the officer catches up with the motorist?
b) What is the officer’s speed at that point?
c) What is the total distance each vehicle has traveled at that point?
Polytechnic University of Puerto Rico
PSE
Physics Tutoring
SCIE 0110 Introduction to Physics
Constant Acceleration
Name _____________________________
Prof. _____________________________
Section _________ Term__________
Tutor William Vélez
(2.21)An antelope moving with constant acceleration covers the distance between two points 70m apart in
7s.Its speed as it passes the second point is 15m/s.
a) What is its speed at the first point?
b) What is its acceleration?
Polytechnic University of Puerto Rico
PSE
Physics Tutoring
SCIE 0110 Introduction to Physics
Constant Acceleration
Name _____________________________
Prof. _____________________________
Section _________ Term__________
Tutor William Vélez
(2.22)The catapult of the aircraft carrier USS Abraham Lincoln accelerates an F/A-18 Hornet jet fighter
from rest to a takeoff speed of 173mi/h in a distance of 307ft.Assume constant acceleration.
a) Calculate the acceleration of the fighter in m/s2.
b) Calculate the time required for the fighter to accelerate to takeoff speed?
Polytechnic University of Puerto Rico
PSE
Physics Tutoring
SCIE 0110 Introduction to Physics
Constant Acceleration
Name _____________________________
Prof. _____________________________
Section _________ Term__________
Tutor William Vélez
(2.31)The graph below shows the velocity of a motorcycle police officer plotted as a function of time.
a) Find the instantaneous acceleration at t = 3s , at t=7s, and t = 11
b) How far does the officer go in the first 5s? The first 9 s? The first 13 s?
Polytechnic University of Puerto Rico
PSE
Physics Tutoring
SCIE 0110 Introduction to Physics
Free Fall
Name _____________________________
Prof. _____________________________
Section _________ Term__________
Tutor William Vélez
(2.6) A one-euro coin dropped from the Leaning Tower of Pisa. It starts from rest and falls freely. Compute
its position and velocity after 1s, 2s and 3s.
Polytechnic University of Puerto Rico
PSE
Physics Tutoring
SCIE 0110 Introduction to Physics
Free Fall
Name _____________________________
Prof. _____________________________
Section _________ Term__________
Tutor William Vélez
(2.7)You throw a ball vertically upward from the roof of a tall building. The ball leaves your hand at a
point even with the roof railing with an upward speed of 15 m/s; the ball is then in free fall. On its way
back down, it just misses the railing. At the location of the building, g=9.8m/s2.
a) Find the position and velocity of the ball 1 s and 4 s after leaving your hand.
b) Find the velocity when the ball is 5 m above the railing.
c) Find the maximum height reached and the time at which it is reached.
d) Find the acceleration of the ball when it is at its maximum height.
Polytechnic University of Puerto Rico
PSE
Physics Tutoring
SCIE 0110 Introduction to Physics
Free Fall
Name _____________________________
Prof. _____________________________
Section _________ Term__________
Tutor William Vélez
(2.40)A lunar lander is making its descent to Moon Base I. The lander descends slowly under the retrothrust of its descent engine. The engine is cut off when the lander is 5 m above the surface and has a
downward speed of 0.8m/s. With the engine off, the lander is in free fall. What is the speed of the lander
just before it touches the surface? The acceleration due to gravity on the moon is 1.6m/s2.