Download Physics Level II-08 - Southington Public Schools

Physics Level II-08
Mid-Term Exam Practice Problems
Directions:
Using the problem solving method, answer each of the following
problems. Place your work and answers on the provided paper. You
may use the following basic equations to solve the problems.
Basic equations:
Basic equations given on exam:
v = d/t
a = ∆v/t
d=
O
sin Ø = ———
H
A
cos Ø = ———
H
vi2 sin2Ø
dx = ———————
a
a = 9.8 m/s2
F
a = ——
m
momentumm·v
1/2 at2
total mtotal· vtotal
impulse = F·t
impulse = ∆ momentum
net momentum (before collision) = net momentum
Work = F·d
Power = work/ time
Fout·dout = Fin·din
PE = mgh
MA = Fout/Fin
MA = din/dout
Fout·rout = Fin·rin
MA = rin /rout
Fout · height = Fin · length
MA =


——
t
length of plane
——————————
height of plane



v = ·r

T = F·d
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m·v2
F = ———
r
(after collision)
g = 9.80m/s2
First Condition of Equilibrium
∑F
parallel
=0
∑F
up
= ∑F
down
Second Condition of Equilibrium
∑T = 0
∑T
Hoop
I = mr2
counterclockwise
=∑T
Solid Cylinder
I = 1/2mr2
clockwise
Solid Sphere
I = 2/5mr2
Problems: Show all work!
1. A snail travels for 24.00 hours at an average speed of 1.05 m/hr. What distance
did it travel?
2. A ball is dropped over a cliff and falls for 12.0 seconds. How far would it fall if the
acceleration due to gravity was 9.80 m/s/s?
3. A long distance runner travels 55 miles in 2.9 hours. What is her average speed?
4. What is the acceleration of a car with a mass of 2,550 kg with an engine that
exerts a force of 45,800 N on the road?
5. A 3,250 kg car accelerates at 15.0 m/s2 for 45.5 seconds. What force was exerted
on the road to cause this acceleration?
6. What is the momentum of an 12.5-kg bowling ball rolling at 1.5 m/s?
7. What impulse occurs when an average force of 105 N is exerted on a cart for
32.0 s?
8. Calculate the work done in lifting a 3255-N safe 2.25 m above the floor.
9. A bar is used to lift a 320-N block of concrete. The pivot is 0.135 m from the
block. If the worker pushes down on the other end of the bar a distance of
2.50 m from the pivot, what force (in N) must he apply?
10. An inclined plane is 32.5 m long and 8.50 m high. What is the mechanical
advantage?
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11. If a force of 85.0 N is applied to a wrench that has a lever arm distance of
0.0103 m, what is the torque?
12. What is the rotational velocity of a merry-go-round that makes 12 complete turns
in 3.30 minutes?
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