Physics Chapter 3
0 m/s
A ball is thrown straight up. At the top of its path its instantaneous speed is
The same as the speed it had when it had when thrown upwards
A ball is thrown upwards and caught when it comes back down. In the absence of air resistance, the speed of the ball when caught would be
The same
A ball is thrown upwards and returns to the same location. Compared with its initial speed its speed when it returns is about
9 m
A ball starting from rest at the top of an inclined plane accelerates at 3 m/s2 and reaches the bottom of the plan in 3 seconds. What is the length of the plane?
2 m/s2
A ball starting from rest at the top of an inclined plane gains a speed of 3 m/s for each second it rolls. What is its acceleration down the incline?
x= 15/.5 x= 30 m/s2
A bicycle travels 15 km in 30 minutes. What is its average speed?
6 m/s2
A car starts from rest and after 7 seconds it is moving at 42 m/s. What is the car's average acceleration?
6 m/s
A car's speed 3 seconds after acceleration from rest at 2 m/s2 is
1 m/s2
A cart changes its speed from 90 m/s to 100 m/s in 10 seconds. During this interval its acceleration is
Acceleration
A free-falling watermelon falls with constant
5 km/h
A humming bird flying at 4 km/h that gets caught in a 3-km/h crosswind has a resultant speed of
x= 40/2 x= 20 m/s2
A jet on an aircraft carrier can be launched from 0 to 40 m/s in 2 seconds. What is the acceleration of the jet?
6 m/s
A mosquito flying at 3 m/s that encounters a breeze blowing at 3 m/s in the same direction has a speed of
141 m
A river 100 m wide flows 1 m/s due south. A boat that travels 1 m/s relative to the water is pointed due east as it crosses from the west bank from the west bank. Relative to its starting pint, the boat travels
The same
A rock dropped from a 5-m height accelerates at 10 m/s2 and strikes the ground 1 s later. If the rock is dropped from a height of 2.5m, its /acceleration/ of fall is
2= x/2 x= 4 m/s
A skateboarder starting from rest accelerates down a ramp 2 m/s2 for 2 s. What is the final speed of the skateboarder?
Changes its direction Gains Speed Loses Speed *All of the above*
A vehicle undergoes acceleration when it
The rate at which velocity itself changes
Acceleration is defined as
Velocity divided by the time interval
Acceleration is defined as the CHANGE in
70 km/h
An 80 km/h airplane fling against a 10 km/h head wind has a ground speed of
100 km/h
An 80-km/h airplane caught in a 60-km/h crosswind has a resultant speed of
90 km/h
An 80-km/h airplane flying in the same direction as a 10 km/h tail wind has a ground speed of
x= .5(10 m/s) x= 5 m/s2
An apple falls from a tree and 0.5 seconds later hits the ground. How fast is the apple falling when it hits the ground?
0 m/s2
An object covers a distance of 8 meters int he first second of travel, another 8 meters during the next second, and 8 meters again during the third second. Its acceleration is
Acceleration increases
As an object falls freely in a vacuum, its
Get further apart
As water drops fall at a steady rate from a leaking faucet they
60 m/s
At one instant in free fall is moving downward at 50 m/s. One second later its speed is
5= 35/x 5x = 35 x= 7s
How much time does a car with an acceleration of 5 m/s2 take to go from 5 m/s to 40 m/s?
6 m/s2
If a car increases its velocity from zero to 60 m/s in 10 seconds, its acceleration is
10 m/s
If a freely falling object were equipped with a speedometer, its speed reading would increase each
180 m
If a stone falls to the bottom of a mineshaft in 6 seconds, then the depth of the shaft is about
Greater than the second before
If an object falling freely were somehow equipped with an odometer to measure the distance it travels, then the amount of distance it travels each succeeding second would be
Change by the same amount each second
If an object moves with constant acceleration, its velocity must
Acceleration
In the absence f air resistance, objects fall at constant
6 m/s
Jogging Jake runs a 4 m/s along a train flatcar that moves at 10 m/s in the opposite direction. Jake's speed relative to the ground is
30 m/s
Neglecting air resistance, how fast must you toss a ball straight up in order for it to take 6 seconds to return to its initial level?
5 m/s
Phil leans over the edge of a cliff and throws a rock upward at 5 m/s. Neglecting air resistance, one second later the rock's speed is
d= (0 m/s)(1.0 s) + (1/2)(6.0 m/s^2)(1.0 s)^2 d= (1/2)(6.0 m/s^2)(1.0 s) d= 3.0 m
Starting from rest, a car undergoes a constant acceleration of 6 m/s2. How far will the car travel in the first second
A larger distance than in the second before
Suppose an object is in free fall. Each second the object falls
Your velocity is constant
Suppose you are in a car that is going around a curve. The speedometer reads a constant 30 miles per hour. Which of the following is NOT true?
Instantaneous speed
The speedometer of an automobile reads
Distance and time
The two measurements necessary for calculating average speed are
More than 100 m/s
Twelve seconds after starting from rest, a free-falling cantelope has a speed of
4 m/s2
What is the acceleration of a car that starts from rest and 5 seconds later reaches a speed of 20 m/s?
x= 88/5 x= 17.6 m/s2
What is the average speed of a cheetah that runs 88 m in 5 seconds?
10 m/s2
When a ball thrown straight upwards reaches the very top of its path, its acceleration is
Instantaneous acceleration
When you look at a speedometer in a moving car, you can see the car's
20 m
When you walk at an average speed of 4 m/s, in 5 s you'll cover a distance of
*Speed* Velocity Acceleration
Which of the following is not a vector quantity
Velocity is not zero
While a car travels around a circular track at a constant speed, its