physics c flashcards

A ball is thrown into the air with an initial velocity of 10 m/s at an angle of 45 degrees above the horizontal, as represented above.

A ball is thrown into the air with an initial velocity of 10 m/s at an angle of 45 degrees above the horizontal, as represented above.

Which of the following representations of the velocity and acceleration of the ball is true?

C. At Highest Point: velocity points to right and acceleration points downwards

A ball is thrown into the air with an initial velocity of 10 m/s at an angle of 45 degrees above the horizontal, as represented above.

If air resistance is negligible, the time needed for the ball to return to the ground is most nearly

B. 1.42s

The figure shows a block on a horizontal surface with the velocity v and acceleration a vectors shown. Which of the following best describes the motion of the box at the moment shown?

C: The block is moving to the right and slowing down.

Figure 1 shows a person dropping a coffee filter to the floor. As the filter drops, air resistance will cause the acceleration to decrease with time. Figure 2 shows the velocity v and acceleration a vectors a short time after the filter is dropped. Which of the following could show the velocity and acceleration vectors a short time after Figure 2?

D: Velocity is largest magnitude and pointing downwards, acceleration is smallest magnitude pointing downwards

In an experiment, a toy car is released from rest and the distance traveled by the car is measured at one second intervals for three seconds. The graph above shows the position as a function of time for the car. Six student representations of the motion of the car are shown below. The first two representations show dots at the position of the car at equal intervals of time. The other four are graphs of different variables as a function of time. Which of the following combinations of representations best represents the above motion?

B: Students 1, 4, and 5

The acceleration vector for the first three seconds of an object moving with constant acceleration is shown. Which of the following motion diagrams best represents the velocity vectors for the first three seconds of the object's motion?

E: V=0, then increasingly larger vectors pointing to the right

A cart is given an initial speed of v0 upward toward a motion detector on a surface of negligible friction that is inclined at an angle θ above the horizontal, as shown in the figure. The data from the motion detector for the position x as a function of time t are shown in the chart. The value of v0 is most nearly

D: 5 m/s

The following data of position x and time t are collected for an object that starts at rest and moves with constant acceleration. (t(s), x(m)) (0, 2), (1, 5), (2, 14), (3, 29). The position of the object at t=5s is most nearly

D: 77 m

In an experiment, a ball is launched vertically upward. A motion sensor is placed directly below the ball as shown so that it can collect data for the height h of the ball and the velocity v of the ball as functions of time t for the trip of the ball upward and back down to its original launch position. Air resistance is negligible. Which of the following shows variables that can be plotted such that it they will create a straight line with a slope approximately equal to the acceleration of the ball?

E: v as a function of t

In an experiment, students measure the position x of a cart as a function of time t for a cart that starts at rest and moves with a constant acceleration. The following data are collected for the cart. (t(s), x(m)) (0, 0), (1, 4), (2, 16), (3, 36), (4, 64). The acceleration of the cart is most nearly

C: 8 m/s^2

A block of mass m is on surface of negligible friction that is inclined at an angle of θ above the horizontal. The block is initially moving up the incline, and its position x as a function of time t is given by the equation x(t)=Mt−Nt^2 , where M has units of m/s and N has units of m/s^2 . The value of t when the block comes to rest is most nearly

B: M/2N

A car is traveling with speed v0 when it begins to speed up at a rate of Δv every second. After t1 seconds, the car travels with zero acceleration for t2 seconds. Which of the following is a correct expression for the displacement of the car during this motion?

D: v0t1 + 1/2(Δv)t1^2+(v0+(Δv)t1)t2

A ball given an initial velocity of v0 at an angle θ above the horizontal. The ball travels up and returns to the same height from which it was released. Possible representations of the motion of the ball are shown below. Which combination of representations correctly represents the vertical component of the ball's motion?

B: II and V

The x and y components of an object's position as a function of time are given by the equations x=2+2t and y=8−2t−5t^2, respectively. The x and y components of the object's velocity as a function of time are

A: vx = 2 and vy = -2 - 10t

An object is sliding along a horizontal table surface of negligible friction with velocity vx when it leaves the end of the table of height H. The object lands a horizontal distance D from the edge of the table. If the object leaves the edge of a horizontal table of height 2H with the same velocity vx, which of the following represents the horizontal distance the object will land from the edge of the new table?

C: sqrt(2)D

An object is moving in a vertical plane. The horizontal and the vertical components vx and vy, respectively, of the object's velocity are given as functions of time by the equations vx=3.0t^2+3.0 and vy=5.0t−1.0 where vx and vy are in m/s. The magnitude of the acceleration of the particle at t=2.0s is most nearly

B: 13 m/s^2

An object is moving in the vertical plane. The magnitude v of the object's velocity as the function of time t is shown in the graph. If the horizontal component of the object's velocity remains constant, which of the following claims best describes the vertical component of the object's velocity?

C: The vertical component is increasing in magnitude at a decreasing rate.

A sling is used to give a stone an initial velocity of 20m/s at an angle of 30° above the horizontal. The stone travels through the air and lands a horizontal distance of 32m from where it was released. If the stone returns to the same height from which it was thrown, which of the following claims best describes the motion of the air through the stone's trajectory?

E: There must be a horizontal wind opposite the direction of the stone's motion, because ignoring air resistance when calculating the horizontal range would yield a value greater than 32m.