Exam 2: Kinematics: Motion in One Dimension

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

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

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?

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?

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,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.Neglect the effects of air.At time $t = 5.97 \mathrm {~s} ,$ the vertical velocity of the ball is closest to

A car starts from rest and accelerates uniformly at 3.0 m/s² toward the north.A second car starts from rest 6.0 s later at the same point and accelerates uniformly at 5.0 m/s² toward the north.How long after the second car starts does it overtake the first car?

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

Two objects are dropped from a bridge,an interval of 1.0 s apart.Neglect air.During the time that both objects continue to fall,their separation

If a car accelerates at a uniform 4.0 m/s²,how long will it take to reach a speed of 80 km/hr,starting from rest?

When is the average velocity of an object equal to the instantaneous velocity?

A ball is thrown straight up with a speed of 36 m/s.How long does it take to return to its starting point,assuming no air?

Which of the following graphs represent an object at rest? (There could be more than one correct choice.) (a) (b) (c) (d) (e)

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 m/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

Ball A is dropped from the top of a building.One second later,ball B is dropped from the same building.Neglect air.As time progresses,the difference in their speeds

A hammer is thrown upward with a speed of 14 m/s on the surface of planet X where the acceleration of object in free fall is 3.5 m/s² and there is no atmosphere.What is the speed of the hammer after 8.0 s?

A child standing on a bridge throws a rock straight down.The rock leaves the child's hand at time t = 0 s.If we take upward as the positive direction,which of the graphs shown below best represents the acceleration of the stone as a function of time?

An object is moving in a straight line with constant acceleration.Initially it is traveling at 16 m/s.Three seconds later it is traveling at 10 m/s.How far does it move during this time?

To determine the height of a flagpole,Abby throws a ball straight up and times it.She sees that the ball goes by the top of the pole after 0.50 s and then reaches the top of the pole again after a total elapsed time of 4.1 s.How high is the pole above the point where the ball was launched? Neglect air resistance.

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 speed?

If the acceleration of an object is zero,then that object cannot be moving.