Physics

1) 8. The graph above shows velocity v versus time for an object in linear motion. Which of the following is a possible graph of postition, x, versus time, t, for this object

A. normal shaped hump graph

1. 6) In the absence of air friction, an object dropped near the surface of the Earth experiences a constant acceleration of about 9.8 m/s². This means that the

A. speed of the object increases about 9.8 m/s during each second

1) 13. A ball is thrown into the air at an angle measured from the horizontal with a velocity v. The horizontal velocity of the ball will be directly proportional to which of the following

C. Cosine of the angle

2) 1. A box is given a sudden push up a ramp. Friction between the box and the ramp is not negligible. Which of the following diagrams best represents the directions of the actual forces acting on the box as it moves upward after the push?

A.

2)13. The cart of mass 10kg shown bove moves without frictional loss on a level table. A 10 N force pulls on the cart horizontally to the right. At the same time, a 30 N force at an angle of 60 degrees above the horizontal pulls on the cart to the left. What is the magnitude of the horizontal acceleration of the cart.

A. 0.5 m/s²

2) 5. The free body diagram shown is for a 5 kg box on a rough surface being pulled to the right at a constant speed by a string that is at an angle of 30 degrees above the horizontal. The coefficient of kinetic friction between the box and the surface is .30. The tension in this string is most nearly

A. 14.47

2) 3. An elevator carrying a person of mass m is moving upward and slowing down. How does the magnitude F of the force exerted on the person by the elevator compare with the magnitude of the gravitational force?

A. F<mg (bc the elevator is slowing down)

1) 11. A rock is dropped from the top of a tall tower. Half a second later another rock, twice as massive as the first, is dropped. Ignoring air resistance,

A. The distance between the rocks increases while both are falling

3) 5. An object attached to one end of a string moves in a circle at a constant speed. Which of the following is correct?

A. The object is accelerating as it moves

2) 11. Box of mass m sits on the floor of an elevator, with box B of mass 2m on top of them, as shown in the figure above. The elevator is moving upward and slowing down. FA is the magnitude of the force exerted on box A by box B, FB is the magnitude of the force exerted on box B by box A, and Fg is the magnitude of the gravitational force exerted on box B. Which of the following ranks the forces in order of increasing magnitude?

B. (FB=FA)<Fg

2) 10. Block A and B, of masses M and 2m, respectively, they, are connected by a light string and pulled across the surface of a negligible Friction with a constant force F1, as shown above. The acceleration of the block is a. The force of the string pulling Block B forward has magnitude of F2. Which of the following claims correctly describes the relationship between the magnitude of the forces acting on the Block?

B. F1 is greater than F2

2) 6. The diagram above represents the forces exerted on a box that a child is holding Fn represents the force applied by the child's hand, and Fg represents the weight of the box. Child begins to raise the box with increasing speed. Which of the following claims is correct about the force Fh that is exerted by the Box on the child's hand as a box of being raised?

B. Fh=Fn where Fn is larger as the box is being raised than when it was held

2) 7. Two blocks are connected by a rope, as shown above. The masses of the blocks are 5kg mg for the upper block and 10 kg for the lower block. An upward applied force of magnitude F acts on the upper block. If the net acceleration is downward but has a magnitude less than G, then which has a larger magnitude, the force f for the tension in the Rope?

B. Force F

1) 10.When a falling object reaches terminal velocity, it

B. Moves downward with a constant velocity

1) 9. Which of the following sets of graphs might be the corresponding graphs of position velocity and acceleration vs time for a moving particle

C. 3 graphs: Position-increasing at a decreasing rate Velocity-linear decreasing Acceleration- constant negative linear

3) 3. A spacecraft is placed in a circular orbit around a planet with mass 6.4x1023g. The spacecraft orbits at a height of 4.5x10⁷m above the planet's surface. What additional information is needed to calculate the speed of the spacecraft in orbit?

B. The planet's radius only

3) 4. A vehicle lands on mars and explore its surface. The average gravitational field on the surface is 3.7 N kg. The weight of the vehicle is defined as the gravitational force exerted on it. Which of the following is true about the vehicle's weight? Select TWO answers

B. The vehicle's weight increased while it was descending to the surface of mars D. The vehicle weighs less on the surface of mars than on the surface of earth

3) 1. A rock attached to a string swings in a vertical circle, as shown above, with negligible air resistance. Which of the following diagrams could correctly show all the forces on the rock when the string is in the position below? (diagram of string parallel to the floor)

C. (3 forces: downward, left, and right)

1) 1. The time it will take the block to reach the ground is most nearly

C. 1.4 s

2) 12. A box of mass m is on a rough inclined plane that is at an angle ∅ with the horizontal. A force of magnitude F at an angle ⊕ with the plane is exerted on the block, as shown above. As the block moves up the plane, there is a frictional force between between the box and the plane of magnitude f. What is the magnitude of the net force acting on the box?

C. Fcos⊕-mgsin∅-f

3) 2. A satellite of mass m and speed v moves in a stable circular orbit around a planet of mass M. What is the radius of the satellite's orbit?

C. GM/v²

2) 14. A book is at rest on top of a table. A student makes the following claim: an attractive electromagnetic force is exerted on the book from the table and this force can also be classified as the normal force. Which statement justifies...

C. The claim is incorrect because the charged particle of the table exert an upward repulsive force on the charged particles of the book

2) 2. A person is running on a track. Which of the following forces propels the runner forward?

C. The force of friction exerted by the ground on the person

2) 4. In an experiment, a student rolls a 2 kg ball such that it collides with a wall with a force of 10000 newtons. In a second experiment, the student roll a 5 kg ball such that it collides with the wall with a force of 5000 N. In both experiments, the balls bounce back from the wall and eventually come to rest. Which of the following statements is true regarding the force that the wall exerts on each ball?

C. The wall exerts a greater force on the 2 kg ball than the 5 kg ball since the force from the wall on each ball is equal to the force that each ball exerts on the wall

1) 15. The graph shows the velocity v as a function of time t for an object moving in a straight line. Which of the following graphs shows the corresponding displacement x as a function of time t for the same interval?

C. very loosely S shaped graph

1) 5.An object slides off a roof 10 meters above the ground The time between the object's leaving the roof and hitting the ground is most nearly

C. √2s

1) 2. Which of the following pairs of graphs represents the vertical components of the velocity and acceleration, v & a respectively, of the projectile functions of time t?

D.

2) 9. The figure above shows the forces exerted on a block that is sliding on a rough horizontal surface colon the weight of the block is 500 Newtons the normal force is 500 Newtons. Frictional force is 100 Newtons there is an unknown Force F exerted to the right. The acceleration of the block is 4 m per second squared. The value F is most nearly

D. 120 N

1) 4. The average speed during the interval between 1s and 2s is most nearly

D. 6 m/s

1. 7) A 500 kg sports car accelerates uniformly from rest, reaching a speed of 30 meters per second in 6 seconds. During the 6 seconds, the car has traveled a distance of

D. 90 m

3) 6. An astronaut stands on the surface of an asteroid. The astronaut jumps such that the astronaut is no longer in contact with the surface. The astronaut falls back down to the surface after a short time interval. Which of the following forces CANNOT be neglected when analyzing the motion of the astronaut?

D. The gravitational force between the astronaut and the asteroid

2) 8. Two identical books are stacked on a table. A third identical book is then placed on top of the first two, causing an increase in the normal force exerted by the bottom on the middle book. Which of the following is a correct explanation for the increase in this normal force?

D. The third book produces an additional downward force on the middle book, thus increasing the upward force exerted by the bottom book to maintain equillibrium

1) 12. An object is shot vertically upward into the air with a positive initial velocity. Which of the following correctly describes the velocity and acceleration of the object at its maximum velocity

D. Velocity: Zero Acceleration: Negative

1) 14.The velocity of a projectile at launch has a horizontal component Vh and a vertical component Vv. Air resistance is negligible. When the projectile is at the highest point of its trajectory, which of the following shows the vertical and horizontal components of its velocity and the vertical component of its acceleration?

E. Vertical velocity: 0 Horizontal Velocity: Vh Vertical acceleration: g

1) 3. How much time does it take the rock to travel from the edge of the building to the ground?

E.√2h/g