Exam 2: Kinematics: Motion in One Dimension

A car is traveling north at 1.77m/s.After 12 s its velocity is $14.1 \mathrm {~m} / \mathrm { s }$ in the same direction.Find the magnitude and direction of the car's average acceleration.

The figure shows a graph of the velocity of an object as a function of time.What is the displacement of the object from 0 s to 6.0 s?

A car is traveling with a constant speed of 30.0 m/s when the driver suddenly applies the brakes,causing the car to slow down with a constant acceleration.The car comes to a stop in a distance of 120 m.What was the acceleration of the car as it slowed down?

A package is dropped from a helicopter that is moving upward at 15 m/s If it takes $8.0 \mathrm {~s}$ before the package strikes the ground,how high above the ground was the package when it was released? Neglect air resistance.

The graph in the figure shows the position of an object as a function of time.The letters H-L represent particular moments of time. (a)At which moment in time is the speed of the object the greatest? (b)At which moment in time is the speed of the object equal to zero?

A bullet shot straight up returns to its starting point in 10 s.What is the initial speed of the bullet,assuming no air?

Suppose a ball is thrown straight up and there is no air.What is its acceleration just before it reaches its highest point?

A toy rocket is launched vertically from ground level at time t = 0 s.The rocket engine provides constant upward acceleration during the burn phase.At the instant of engine burnout,the rocket has risen to 49.0 m and acquired an upward velocity of 60.0 m/s.The rocket continues to rise with insignificant air resistance in unpowered flight,reaches maximum height,and falls back to the ground.The maximum height reached by the rocket is closest to

A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h.What is her average speed for the trip?

A bicyclist starts a timed race at $6.0 \mathrm { mi } / \mathrm { h } .$ In order to win,he must average $21 \mathrm { mi } / \mathrm { h } .$ Assuming constant acceleration from the start,how fast must he be traveling at the end of the race?

Car A is traveling at 22.0 m/s and car B at 29.0 m/s.Car A is 300 m behind car B when the driver of car A accelerates his car with a uniform forward acceleration of 2.40 m/ $\mathrm { s }^2$ How long after car A begins to accelerate does it take car A to overtake car B?

If the velocity versus time graph of an object is a horizontal line,the object is

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

A racing car accelerates uniformly from rest along a straight track.This track has markers spaced at equal distances along it from the start,as shown in the figure.The car reaches a speed of 140 km/h as it passes marker 2. Where on the track was the car when it was traveling at half this speed,that is at 70 km/h?

To determine the height of a bridge above the water,a person drops a stone and measures the time it takes for it to hit the water.If the height of the bridge is 41 m,how long will it take for the stone to hit the water? Neglect air resistance.

If the position versus time graph of an object is a horizontal line,the object is

The graph in the figure shows the position of a particle as a function of time as it travels along the x-axis. (a)What is the magnitude of the average velocity of the particle between t = 1.0 s and t = 4.0 s? (b)What is the average speed of the particle between t = 1.0 s and t = 4.0 s?

The slope of a position versus time graph gives

If the velocity of an object is zero at one instant,what is true about the acceleration of that object? (There could be more than one correct choice.)

You are driving home on a weekend from school at 55 mi/h for 110 miles.It then starts to snow and you slow to 35 mi/h.You arrive home after driving 4 hours and 15 minutes.How far is your hometown from school?