Exam 2: Motion in One Dimension

A motorist makes a trip of 180 miles. For the first 90 miles she drives at a constant speed of 30 mph. At what constant speed must she drive the remaining distance if her average speed for the total trip is to be 40 mph?

The graph in the figure shows the position of a particle as it travels along the x-axis. What is the magnitude of the instantaneous velocity of the particle when t = 1.0 s?

Which of the following quantities has units of a velocity? (There could be more than one correct choice.)

An auto manufacturer advertises that their car can go "from zero to sixty in eight seconds." This is a description of what characteristic of the car's motion?

A bat, flying toward the east at 2.0 m/s, emits a shriek that is reflected back to it from a wall that is 20.0 m in front of the bat at the instant the shriek is emitted. Sound travels at 340 m/s in the air. How many milliseconds after emitting the shriek does the bat hear the reflected echo from the wall?

A car increases its forward velocity uniformly from 40 m/s to 80 m/s while traveling a distance of 200 m. What is its acceleration during this time?

Two athletes jump straight up. John has twice the initial speed of Harry. Compared to Harry, John stays in the air

An object is moving with constant non-zero acceleration in the +x direction. The velocity versus time graph of this object is

The figure shows a graph of the position of a moving object as a function of time. What is the velocity of the object at each of the following times? (a)At t = 1.0 s (b)At t = 2.5 s (c)At t = 4.0 s (d)At t = 5.5 s

A bullet shot straight up returns to its starting point in 10 s. What is the initial speed of the bullet, assuming negligible air resistance?

If the velocity of an object is zero, then that object cannot be accelerating.

A laser is thrown upward with a speed of 12 m/s on the surface of planet X where the acceleration due to gravity is 1.5 m/s² and there is no atmosphere. What is the maximum height reached by the laser?

Which of the following graphs represent an object at rest? (There could be more than one correct choice.) A. B. C. D. E.

You drive 6.0 km at 50 km/h and then another 6.0 km at 90 km/h. Your average speed over the 12 km drive will be

An astronaut stands by the rim of a crater on the Moon, where the acceleration of gravity is 1.62 m/s² and there is no air. To determine the depth of the crater, she drops a rock and measures the time it takes for it to hit the bottom. If the depth of the crater is 120 m, how long does it take for the rock to fall to the bottom of the crater?

Human reaction times are worsened by alcohol. How much further (in feet)would a drunk driver's car travel before he hits the brakes than a sober driver's car? Assume that both are initially traveling at 50.0 mi/h and their cars have the same acceleration while slowing down, and that the sober driver takes 0.33 s to hit the brakes in a crisis, while the drunk driver takes 1.0 s to do so. (5280 ft = 1 mi)

The slope of a position versus time graph gives

The graph in the figure shows the position of a particle as it travels along the x-axis. At what value of t is the speed of the particle equal to 0 m/s?

Which of the following situations is impossible?

The figure shows a graph of the velocity of an object as a function of time. What is the average acceleration of the object over the following time intervals? (a)From t = 0 s to t = 5.0 s (b)From t = 0 s to t = 8.0 s