tennis ball launchers. One person launches her tennis ball with a speed of 30 m/s at an angle of 45 degrees above the

Don't need to show or explain work, just need the answers. 10 questions here.

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1. A certain vector has x, y components that are equal in magnitude and a z component that is zero. Which of the following is a possible angle for this vector, in a standard x-y-z coordinate system?
A)  30° B)  45° C)  90° D)  180°  E)  60°

2. Two people stand on the edge of a cliff with tennis ball launchers. One person launches her tennis ball with a speed of 30 m/s at an angle of 45 degrees above the horizontal, while the other person launches his tennis ball from the same height and at the same time with a velocity of 30 m/s directed at an angle of 45 degrees below the horizontal. Which tennis ball has the greater velocity when it hits the ground below the cliff? Ignore air resistance.

A)  the tennis ball launched upward

B)  the tennis ball launched downward

C)  whichever tennis ball was heavier 

D)  whichever is fluffier 

E)  neither – they both have the same velocity on impact

3. In a collision between a taxi and a bicyclist, the ___________ experiences the greater force and the _____________ experiences the greater acceleration.

A)  bicyclist; bicyclist

B)  the taxi; taxi

C)  both have the same force; bicyclist has the greater acceleration

D)  bicyclist has greater force; both have same acceleration

4. Beta-minus decay of 40K results in

A)  41Ca B)  40Ca C)  39Ca D)  41K E)  40K F) 39K

5. There are 2 protons and 2 neutrons in an alpha particle, Why doesn’t the alpha particle burst apart?

A) The Coulomb force attracts the protons to the neutrons and holds the alpha particle together.

B) The Coulomb force attracts the neutrons to each other and holds the alpha particle together.  

C)  Another force besides the Coulomb force exists inside the alpha particle and holds it together.

D)  The Coulomb force attracts the protons to each other and holds the alpha particle together.

E)  Gravity overpowers the Coulomb repulsive force inside the alpha particle

F) All of the above are true.

G) It is actually unstable, half of the free alpha particles shall actually decay in 15 minutes

6. Wave-Particle duality is most noticeable for

A)  Extremely dense objects like black holes

B)  Electrons, but only in wires

C)  Extremely large objects like starts

D)  Extremely small objects like electrons

E)  Any object that is completely isolated from all external forces

F)  All of the above

G)  None of the above

6. Two objects collide and stick together. If the objects have initial momentum magnitudes of 10 kg m/s and 15 kg m/s, which of the following could be the magnitude of the final momentum? (Remember that momentum is a vector!)

A) 0 kg m/s B) 4 kg m/s C) 8 kg m/s D) 20 kg m/s

B) 25 kg m/s F) 30 kg m/s G) 2 of the above H) 3 of the above

C) 4 of the above J) All of the above K) None of the above

7. The area enclosed by a thermodynamic cycle on a pressure vs. volume graph is equal to

A)  The efficiency of the cycle

B)  The work done during the cycle

C)  The energy wasted during the cycle

D)  The change in temperature of the system

E)  The input energy required to perform one cycle


8. A large uranium nucleus initially at rest splits into two large fragments. What can you say about the combined total momentum and kinetic energy of the two significant fragments?

A)  The total momentum and total kinetic energy are both zero.

B)  The total momentum and total kinetic energy are greater than zero

C)  The total momentum is greater than zero and the total kinetic energy is zero.

9. An electron is accelerated through a voltage until it has 10 times its initial speed. By what factor has its kinetic energy changed?

A) 1/100 B) 1/10 C) 1 (it stays the same) D) 10 E) 100

B) It does not have a kinetic energy

C) It only has non-zero momentum

D) None of the above

E) All of the above

F)  The total momentum is zero and the total kinetic energy is greater than zero.

G)  Impossible to say without more information.

H)  It actually splits into more than two fragments

I)  None of the above

J)  All of the above

10. When performing a double-slit experiment, it is possible to observe interference when using:

A)  Waves

B)  Particles

C)  All of the above

D)  None of the above