Exam 2: Motion in One Dimension

In the absence of air resistance, a ball is thrown vertically upward with initial speed v. An identical ball is thrown upward with initial speed 2v. If the first ball reaches a maximum height h, what maximum height will the second ball reach?

A stone is thrown with an initial upward velocity of 7.0 m/s and experiences negligible air resistance. If we take upward as the positive direction, what is the velocity of the stone after 0.50 s?

A runner runs around a track consisting of two parallel lines 96 m long connected at the ends by two semicircles with a radius of 49 m. She completes one lap in 100 seconds. What is her average velocity?

When a ball is thrown straight up with no air resistance, the acceleration at its highest point

A car travels at 15 m/s for 10 s. It then speeds up with a constant acceleration of 2.0 m/s² for 15 s. At the end of this time, what is its velocity?

The graph in the figure shows the velocity of a particle as it travels along the x-axis. What is the magnitude of the average acceleration of the particle between t = 1.0 s and t = 4.0 s?

A train starts from rest and accelerates uniformly until it has traveled 5.6 km and acquired a forward velocity of $42 \mathrm {~m} / \mathrm { s }$ The train then moves at a constant velocity of $42 \mathrm {~m} / \mathrm { s }$ for 420 s. The train then slows down uniformly at $0.065 \mathrm {~m} / \mathrm { s } ^ { 2 }$ until it is brought to a halt. The acceleration during the first 5.6 km of travel is closest to which of the following?

The figure shows a graph of the position of a moving object as a function of time. (a)What is the average velocity of the object from t = 0 s to t = 4.0 s? (b)What is the average velocity of the object from t = 0 s to t = 6.0 s?

Starting from rest, a dragster travels a straight 1/4 mi racetrack in 6.70 s with constant acceleration. What is its velocity when it crosses the finish line?

A rock from a volcanic eruption is launched straight up into the air with no appreciable air resistance. Which one of the following statements about this rock while it is in the air is correct?

A car is moving with a speed of 32.0 m/s. The driver sees an accident ahead and slams on the brakes, causing the car to slow down with a uniform acceleration of magnitude 3.50 m/s². How far does the car travel after the driver put on the brakes until it comes to a stop?

A toy rocket is launched vertically from ground level at time t = 0.00 s. The rocket engine provides constant upward acceleration during the burn phase. At the instant of engine burnout, the rocket has risen to 64 m and acquired an upward velocity of $60 \mathrm {~m} / \mathrm { s }$ The rocket continues to rise with insignificant air resistance in unpowered flight, reaches maximum height, and falls back to the ground. The time interval during which the rocket engine provided the upward acceleration, is closest to

A rock is projected upward from the surface of the Moon, at time t = 0 s, with an upward velocity of 30.0 m/s. The acceleration due to gravity at the surface of the Moon is 1.62 m/s², and the Moon has no atmosphere. The height of the rock when it is descending with a speed of 20.0 m/s is closest to

A car with good tires on a dry road can decelerate (slow down)at a steady rate of about 5.0 m/s² when braking. If a car is initially traveling at 55 mi/h (a)how much time does it take the car to stop? (b)what is its stopping distance?

Consider a deer that runs from point A to point B. The distance the deer runs can be greater than the magnitude of its displacement, but the magnitude of the displacement can never be greater than the distance it runs.

A ball is projected upward at time t = 0 s, from a point on a flat roof 10 m above the ground. The ball rises and then falls with insignificant air resistance, missing the roof, and strikes the ground. The initial velocity of the ball is $58.5 \mathrm {~m} / \mathrm { s }$ Consider all quantities as positive in the upward direction. At time $t = 5.97 \mathrm {~s} ,$ the vertical velocity of the ball is closest to

A 10-kg rock and 20-kg rock are dropped from the same height and experience no significant air resistance. If it takes the 20-kg rock a time T to reach the ground, what time will it take the 10-kg rock to reach the ground?

If the velocity versus time graph of an object is a straight line making an angle of +30° (counter clockwise)with the time axis, the object is

A polar bear starts at the North Pole. It travels 1.0 km south, then 1.0 km east, and then 1.0 km north to return to its starting point. This trip takes 45 min. What was the bear's average speed?

Brick A is dropped from the top of a building. Brick B is thrown straight down from the same building, and neither one experiences appreciable air resistance. Which statement about their accelerations is correct?