Physics Final Exam Review 2 Problem Solving Solve the following

Transcription

Physics Final Exam Review 2 Problem Solving Solve the following
Physics Final Exam Review 2
Problem Solving
Solve the following problems on a separate sheet of paper. Show all of your work and pay attention to
significant figures and units.
1. How many significant digits are in the following measurements?
a. 2.546 m 4
b. 3000 m 1
c. 4.3040 m 5
d. 302 m 3
e. 0.000450 m 3
2. Write the following measurements in scientific notation.
a. 2430 m 2.43 x 103
b. 0.0004240 m 4.24 x 10-4
c. 40,000 m 4 x 104
d. 46.0 m 4.60 x 101
e. 0.000000008780 m 8.780 x 10-9
3. Complete the missing parts of the chart.
Symbol
Prefix
Power of 10
G
giga-
109
M
mega-
106
k
kilo-
103
h
hecto-
102
da
deca-
101
d
deci-
10-1
c
centi-
10-2
m
milli-
10-3
µ
micro-
10-6
n
nano-
10-9
4. A bike travels at a constant speed of 4.00 m/s for 5.00 seconds. How far does it go? 20.0 m
5. You and a friend each drive 50.0km. You travel at a speed of 100.0km/hr; your friend travels at a
speed of 125.0km/hr. How long (in minutes) will your friend have to wait for you at the end of the trip
if you leave at the same time? 0.100hr = 6.00 min
6. A car is moving down the street at 55km/h. A child suddenly runs into the street. If it takes the driver
0.75 seconds to react and apply the brakes, how many METERS will the car have moved before it
begins to slow down? 11 m
7. A roller coaster car rapidly picks up speed as it rolls down a slope. As it starts down the slope, its speed
is 4.0 m/s. But 3.0 seconds later, at the bottom of the slope, its speed is 22 m/s. What is its average
acceleration? 6.0 m/s
8. If a Ferrari, with an initial velocity of 10.0 m/s, accelerates at a rate of 50.0 m/s 2 for 3.00 seconds, what
will its final velocity be? 160. m/s = 1.60 x 102 m/s
9. An object falls from a high building. Ignoring air resistance, what will its velocity be after 6.00 seconds
of falling? 58.8 m/s
10. During a tornado in 2008 the Peachtree Plaza Westin Hotel in downtown Atlanta suffered damage.
Suppose a piece of glass dropped near the top of the hotel falling 215 meters.
a. Ignoring air resistance, how long would it take the piece of glass to hit the ground? 6.62 s
b. Ignoring air resistance, what will the velocity of the piece of glass be when it strikes the ground?
64.9 m/s
11. You place a watermelon on a spring scale in the grocery store. If the mass of the watermelon is 4.0 kg,
what is the reading of the scale in Newtons? 39 N
12. A little girl wants to learn how to ice skate. She wants her mother to pull her along so that she has an
acceleration of 0.80 m/s2. If her mass is 27.2 kg, with what force does the mother need to pull ignoring
friction? 21.8 N
13. Terri and Jean simultaneously grad a 0.75 kg piece of rope and begin pulling it in opposite direction. If
Terri pulls with a force of 16.0 N and the rope accelerates away from her at 1.25 m/s2, with what force
is Jean pulling? 16.9 N
14. Two shoppers walk from the door of the mall to their car, which is 250.0 m down a lane of cars, and
then they turn 90.0o to the right and walk an additional 60.0 m to their car. What is the magnitude of
the displacement of the shoppers’ car from the mall door? 257 m
15. You push a 25.0 kg wooden box across a wooden floor at a constant speed. If the coefficient of kinetic
friction between two wooden objects is 0.50, how much force do you exert on the box? 120 N 2 sig fig
16. You help your mom move a 41 kg bookcase to a different place in the living room. If you push with a
force of 65 N and the bookcase accelerates at 0.12 m/s2, what is the coefficient of friction between the
bookcase and the carpet? 0.15
17. A ball is thrown horizontally at 8.5 m/s from the top of a 55 m cliff. How far from the base of the cliff
would the ball land? 28 m
18. A rock is thrown horizontally from the top of a 22.0 m hill and lands a distance of 33.0 m from the base
of the hill. How fast was the rock thrown? 15.6 m/s
19. A 550 kg car accelerates from 15 m/s to 25 m/s in 15 s by applying a constant force. How large of a
force is exerted? 370 N 2 sig fig
20. A 78 kg defensive back moving 8.5 m/s tackles a 72 kg receiver moving at 7.5 m/s. What is the postcollision speed immediately after the tackle? 8.0 m/s