FearOfPhysics.com: Position, velocity, and acceleration

[1] You sneeze while you are driving, and your eyes close for about 0.5 seconds
during the sneeze. If you are driving at **km/hr** , how far does the car move during that time?

[2] An object has a constant acceleration of **m/s ^{2}** . At a certain instant its
velocity is

[3]A car increases its speed from **km/hr** to
**km/hr** in **minutes** .
What is the acceleration of the car?

[4]In order to take off, an airplane must reach a speed of **km/hr** on the runway.
What is the least constant acceleration it can have in order to take off from a runway
**km** long?

[5] In good driving conditions (dry road, etc.), the brakes on a car with new tires can
decelerate the car (slow it down) at **m/s ^{2}** . If the car is traveling at

[6] A car starts from rest and coasts down a hill with a constant acceleration. If it goes **meters** in **seconds** ,
find the acceleration and the velocity after this time.

[7] A car's velocity changes from **m/s** to **m/s** while covering **meters** . What is the acceleration of the car and the time it takes to do this?

[8]A ball is dropped from a bridge and strikes the water in **seconds** . How fast is it moving
when it strikes the water, and what is the height of the bridge (neglect air resistance)?

[9]With what speed must a ball be thrown vertically upward to rise to a maximum height of **meters** ? And, how long will it be in the air?

[10]You are speeding on the freeway going **miles per hour** . You see a police car
with its radar gun pointed right at you, and you try to slow down quickly. Your car's brakes
give you an deceleration of 17 ft/s^{2} (a realistic number). How long will it take you to slow down to 55 miles per hour?
Is it worth even trying to slow down?

[11]At the instant a traffic light turns green, a car starts from rest and accelerates at **m/s ^{2}** . At this same
instant, a truck overtakes the car traveling at the constant speed of

[12]You drop a rock from rest from a bridge and note that it hits the ground below
**seconds** later. How high is the bridge?

[13]You throw a rock straight down at **m/s** from a bridge and note that it hits the ground below
**seconds** later. How high is the bridge?

[14]Two trains are mistakenly heading toward each other. Train #1 is going at **km/hr** and train #2
is going **km/hr** . They see each other and begin braking when they are **km** apart.
Train brakes provide a stopping acceleration of **m/s ^{2}** . Is there are collision?

[15]You are standing on top of a building **meters** high, and throw a ball straight upward with
a velocity of **m/s** . On the way down, the ball misses the building's top and falls to the
ground. How long does it take to reach the ground, and how fast is the rock moving when it hits the ground?

[16]A truck starts from rest and moves with a constant acceleration of **m/s ^{2}** . Find its
speed and distance traveled after

[17]A box slides down an incline with uniform acceleration. It starts from rest and attains a speed of **m/s** in
**seconds** . What is the acceleration of the block, and the distance it moves in the first **seconds** ?

[18]A train running at **m/s** is slowed uniformly to a stop in **s** . Find the
acceleration and the stopping distance of the train.

[19]A ball is thrown upward and returns to its starting point in **seconds** . Find its initial speed.

[20]\symbollook{middle,25}
A truck is moving at **m/s** . The driver suddenly sees a vacant car blocking its path
**meters** straight ahead. After a "reaction time" \bigdelta t, the driver applies
the brakes, which gives the truck a deceleration of **m/s ^{2}** . What is the minimum
\bigdelta t, or "reaction time" the driver can have, to stop in time, and not hit the car?