Practice Test #1
Supplemental Instruction
IowaStateUniversity / Leader: / Wesley Hutter
Course: / PHYS 221
Instructor: / Canfield/Herrera-Siklody
Date: / 10/01/2013

DO NOT LOOK AT THIS PRACTICE TEST UNTIL IT IS TIME TO TAKE IT!!!

ONLY print it off and bring it with you to the SI exam review on Tuesday, October 1st.

  1. Let a vector A = 4i + 7j – 6k and vector B = ai+ 1j + 9k. Find the value of a so that A and B are perpendicular to each other.
  1. 11.75
  2. 17.25
  3. 10
  4. 25
  5. π
  6. I has the dumb, and I can’t math today.
  1. A bank robber drives down the road at a constant speed of 60 m/s. A police car is parked, at rest, until the robber speeds past. At the moment the robber passes the cop, the policeman accelerates at a constant acceleration of 9 m/s2. How far does the robber travel before the policeman catches up to him?
  1. 2 m
  2. 390 m
  3. 490 m
  4. 650 m
  5. 800 m
  6. I let the bank robber escape by allowing him to take shelter in my garage in return for a share of his booty.
  1. A cat is trapped on the end of one of the 75.0 cm-long blades of a ceiling fan while the fan has an angular acceleration that is modeled by the term α(t) = (3.00 rad/s3)t. What is the magnitude of the cat’s total acceleration at t = 1.50s if the fan is at rest at t = 0.00 s?
  1. 1.2 m/s2
  2. 14.3 m/s2
  3. 9.19 m/s2
  4. 3.45 m/s2
  5. 45.9 m/s2
  6. I would rather save my cat than solve this physics problem.
  1. You push a 5 kg box is pushed across a floor by a 100 N force as shown below. If the coefficient of kinetic friction between the box and the floor is 0.30, what is the acceleration of the box?
  1. 11.4 m/s2
  2. 11 m/s2
  3. 4.08 m/s2
  4. 4.1 m/s2
  5. 5.2 m/s2
  6. I would be smart and carry the box rather than push it along the ground.

  1. A mass m is attached to a rope that rises vertically, passes over a pulley, and then extends horizontally to another mass (or a wall). Which rope will be under the most tension? Assume that the rope is massless, and that the pulley is massless and frictionless.

E. All ropes have equal tensions.

F. I assume that the entire apparatus in each scenario is in free-fall, and that the tension in all of the ropes is zero.

  1. A 2.0 kg block is placed on top of a 5.0 kg block. The coefficients of friction between them are μk = 0.30 and μs = 0.40. The whole system is on a frictionless horizontal surface. A horizontal force of F = 15 N is applied on the bottom block. What is the magnitude of the frictional force between the two blocks?
  1. 13 N
  2. 5.9 N
  3. 2.0 N
  4. 7.8 N
  5. 10 N
  6. Physics is hard.
  1. When doing a pull-up, your mother lifts her body of 50 kg a distance of 0.25 m in 2 seconds. What is the power delivered by her biceps?
  1. 250 W
  2. 251 W
  3. 300 W
  4. 310 W
  5. 400 W
  6. OVER 9,000 W!!! … And my mom’s awesome.