Exam 3: Acceleration

An object starts from rest at time t = 0.00 s and moves in the +x direction with constant acceleration. The object travels 12.0 m from time t = 1.00 s to time t = 2.00 s. What is the acceleration of the object?

A car accelerates from 10.0 m/s to 30.0 m/s at a rate of 3.00 m/s². How far does the car travel while accelerating?

A block is given a very brief push up a 20.0° frictionless incline to give it an initial speed of 12.0 m/s. (a) How far along the surface of the plane does the block slide before coming to rest? (b) How much time does it take to return to its starting position?

A rock is thrown directly upward from the edge of the roof of a building that is 66.2 meters tall.The rock misses the building on its way down,and is observed to strike the ground 4.00 seconds after being thrown.Neglect any effects of air resistance.With what speed was the rock thrown?

The position of an object as a function of time is given by x(t)= at³ - bt² + ct - d,where a = 3.6 m/s³, b = 4.0 m/s²,c = 60 m/s,and d = 7.0 m. (a)Find the instantaneous acceleration at t =2.4 s. (b)Find the average acceleration over the first 2.4 seconds.

Two identical objects A and B fall from rest from different heights to the ground and feel no appreciable air resistance. If object B takes TWICE as long as object A to reach the ground,what is the ratio of the heights from which A and B fell?

The figure shows the velocity of a particle as it travels along the x-axis.What is the direction of the acceleration at t = 0.5 s?

A runner maintains constant acceleration after starting from rest as she runs a distance of 60.0 m. The runner's speed at the end of the 60.0 m is 9.00 m/s. How much time did it take the runner to complete the 60.0 m distance?

The acceleration of an object as a function of time is given by a(t)= (3.00 m/s³)t,where t is in seconds. If the object is at rest at time t = 0.00 s,what is the velocity of the object at time t = 6.00 s?

A foul ball is hit straight up into the air with a speed of 30.0 m/s. (a)Calculate the time required for the ball to rise to its maximum height. (b)Calculate the maximum height reached by the ball. (c)Determine the time at which the ball pass a point 25.0 m above the point of contact between the bat and ball. (d)Explain why there are two answers to part (c).

A soccer ball is released from rest at the top of a grassy incline.After 8.6 seconds,the ball travels 87 meters and 1.0 s after this,the ball reaches the bottom of the incline. (a)What was the magnitude of the ball's acceleration,assume it to be constant? (b)How long was the incline?

If an object is accelerating toward a point,then it must be getting closer and closer to that point.

Suppose that a car traveling to the west (the -x direction)begins to slow down as it approaches a traffic light.Which statement concerning its acceleration in the x direction is correct?

A package is dropped from a helicopter moving upward at 15 m/s.If it takes 16.0 s before the package strikes the ground,how high above the ground was the package when it was released if air resistance is negligible?

If the graph of the position as a function of time for an object is a horizontal line,that object cannot be accelerating.

A ball is projected upward at time t = 0.00 s,from a point on a roof 70 m above the ground and experiences negligible air resistance.The ball rises,then falls and strikes the ground.The initial velocity of the ball is 28.5 m/s.Consider all quantities as positive in the upward direction.The velocity of the ball when it is 39 m above the ground is closest to

The figure shows the position of an object (moving along a straight line)as a function of time.Assume two significant figures in each number.Which of the following statements about this object is true over the interval shown?

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 70 km/h?

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? (You can ignore air resistance.)

A toy rocket is launched vertically from ground level (y = 0.00 m),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 72 m and acquired a velocity of 30 m/s.The rocket continues to rise in unpowered flight,reaches maximum height,and falls back to the ground with negligible air resistance.The speed of the rocket upon impact on the ground is closest to