1.
An object slides on a frictionless surface into a normal spring, as shown, compressing the spring. During the
compression, the spring compresses a total distance of d, from its relaxed position. When the object is has
compressed the spring a distance of d/2, which is true regarding energy
magnitude?
a. KEobject<Us
b. KEobject=Us
c. KEobject>Us
d. The energy relationship between kinetic and potential energy, cannot
be
determined without the mass of the object.
e. The energy relationship between kinetic and potential energy cannot be determine without the spring
constant.
2.
A ball on a string falls from rest at position a through position b. Which of the
following is true?
a. Gravity does negative work
b. Tension does negative work
c. Gravity does positive work
d. Tension does positive work
e. No work is done by either gravity or tension
3.
If a potential energy function is given by U(r) = br-3/2 + c, where b and c are constants and r is distance, which of the
following is an expression for the force on the particle?
a.
b.
c.
d.
e.
4.
3b 1 / 2
r
2
3b 5 / 2
r
2
3 1/ 2
r
2
2br 1/ 2  cr
2 b 5 / 2
r
 cr
5
An object is sliding up a ramp, as shown, with a frictionless surface. At the position shown, the object has a kinetic
energy of 3J, and a potential energy of 1J (relative to the bottom of the ramp). What will be the total distance from
the bottom of the ramp (point a) to
the furthest location the object moves
up the ramp? (you are solving for the
distance along the slope, not vertical)
a. 2m
b. 4m
c. 8m
d. 12m
e. 16m
5.
A mass is pulled on a frictionless surface by two light springs. The mass has no movement. The spring constant of
K1<K2. How can we compare F1 and F2, Us1 and
Us2, respectively?
a. F1<F2, Us1<Us2
F1>F2, Us1>Us2
b.
F1=F2, Us1< Us2
c.
F1=F2, Us1=Us2
d.
e. F1=F2, Us1>Us2
6.
Which of the following best represents the potential energy of a spring as a function of the distance stretched from
the relaxed position?
7.
What is the speed of the falling block after a 2.5 meter drop? Assume the system is
frictionless, the top block is still on the table, and the pulley is very light. Both
blocks have a mass of 1Kg.
a. 1
b. 2
c. √2
d. 5
e. 5√2
8.
During an archery lesson at gateway high school, an arrow is loosed towards the target 40meters away and 10meters
above foot level. The arrow hits the target at 30m/s. The arrow has a mass of .2Kg. Air and its effects present.
a. At point P designate the direction of acceleration of the arrow considering the forces acting on the arrow.
Justify
b.
If the arrow lost 12.5J of energy to air resistance during flight, calculate the speed of the arrow as it was
loosed by the bow.
The arrow is stopped by the hay behind the target. Assuming force of resistance of the hay has a direct and linear
proportionality to the distance the arrow is embedded in the hay. Assume that the forces of resistance acting on the arrow
during removal will be the same in magnitude to the resistance when entering. It takes 80N of force to start removing the
arrow.
c.
Determine the penetration distance of the arrow.
In a new situation, we fire two arrows at the same speed. One is fired at a large angle (high in the air) while the
second arrow was fired at a lower angle, both hitting the target in the same location.
d. With air resistance considered, the impact speed of the higher trajectory arrow will be (less than, equal to,
greater than) the lower trajectory arrow. Justify your answer.
e.
Neglecting air resistance, the impact speed of the higher trajectory arrow will be (less than, equal to,
greater than) the lower trajectory arrow. Justify your answer.
A 5-kilogram object initially slides with speed vo in a hollow frictionless pipe. The end of the pipe contains two springs, one
nested inside the other, as shown above. The object makes contact with the inner spring at point A, moves 0.1 meter to make
contact with the outer spring at point B, and then moves an additional 0.05 meter before coming to rest at point C. The graph
shows the magnitude of the force exerted on the object by the springs as a function of the objects distance from point A.
a. Calculate the spring constant for the inner spring.
b. Calculate the decrease in kinetic energy of the object as it moves from point A to point B.
c. Calculate the additional decrease in kinetic energy of the object as it moves from point B to point C.
d.
Calculate the initial speed vo of the object
e.
Calculate the spring constant of the outer spring