Module 4 Quizzes Flashcards
A 3.0 kg box initially at rest is suddenly pulled to the right along a level (rough) surface in the positive x-direction with a constant force of 25 N. If the force of friction is 4.0 N and constant, what is the velocity of the box after 1.0 s?
A. 6.0 m/s
B. 9.7 m/s
C. 8.3 m/s
D. 7.0 m/s
D
Suppose Keisha hopped on a scale and weighted 539 N here on earth. If she then weighs herself on planet X where the free-fall acceleration is 4.20 m/s^2, what is her weight on planet X?
A. 55 N
B. 128 N
C. 231 N
D. 307 N
C
A small child pushes on a couch at an angle theta below the horizontal, but the couch remains at rest. Which of the following is not a force acting on the couch?
A. Gravity
B. Air resistance
C. Normal force
D. Friction
B
While blasting off of planet Glorg’s atmosphere, Now traveling through space, which best describes the ship’s motion?
A. It continues to accelerate away from planet Glorg.
B. It travels at a constant speed away from the planet Glorg.
C. It slows down and eventually stops.
D. It slows down and eventually begins to fall back towards planet Glorg.
D
Three old cars of equal mass m sit on top of each other in a junkyard. Which best describes the forces on the middle car?
A. w = -mg, n = +2mg, F = -mg
B. w = -mg, n = +mg
C. w = +mg, n = +mg
D. w = +mg, n = -2mg, F = +mg
A
The Sun has about 1000 the mass of Jupiter. Which best describes the gravitational forces between the Sun and Jupiter?
A. The Sun attracts Jupiter, but not the other way around.
B. The Sun attracts Jupiter with a force 1000 times that of Jupiter.
C. The Sun attracts Jupiter with a force about 32 times that of Jupiter.
D. They both experience the same attractive gravitational force.
D
Ayla hangs a 7.3 kg bowling ball from the ceiling by a rope of negligible mass. The rope will break if the tension in the rope exceeds 110 N. What minimum force must Ayla’s dog Rufus exert on the bowling ball to break the rope.
A. 72 N B. 103 N C. 48 N D. 38 N
D
A block of mass m sits at rest on a plane inclined at angle x. What is the magnitude of the static friction force on the block? (Diagram is on canvas)
A. mg sin x
B. mg cos x
C. mg
D. mg tan x
A
Atwood’s machine has two masses attached by a string suspended over a pulley, If the masses are released from rest?
(drawing is on canvas)
A. m1 accelerates upwards at 9.8 m’s^2
B. m2 accelerates downwards at 9.8 m/s^2
C. m2 accelerates downwards at 4.0 m/s^2
D. m2 accelerates downwards at 5.7 m/s^2
C
A man on a scale sitting in an elevator, which initially at rest. After the doors of the elevator close, the man’s weight indicated by the scale begins to increase. Which of the following is correct?
A. The elevator is traveling upwards at a constant speed.
B. The elevator is accelerating upwards.
C. The elevator is traveling downwards at a constant speed.
D. The elevator is accelerating downwards.
B
