Fizx First Fall Final Study Guide
A car accelerates from rest at 2 meters per second per second. What is its speed 3 seconds after the car starts moving?
6 m/s
A car starts from rest after 7 seconds it is moving at 42 m/s. What is the car's average acceleration?
6 m/s
If a projectile is fired straight up at a speed of 30 m/s, the total time to return to its starting point is about
6 s
A ball is hurled into the air at an angle of 30 degrees and lands on a target that is at the same level as that where the ball started. The ball will also land on the target if it is thrown at an angle of
60 degrees
Suppose you take a trip that covers 180 km and takes 3 hours to make. Your average speed is
60 km/hr
A freely falling object starts from rest. After falling for 6 seconds, it will have a speed of about
60 m/s
A bullet is dropped from the top of the Empire State Building while another bullet is fired downward and is out of the gun from the same location. Neglecting air resistance, acceleration is greatest for the
neither it's -10 m/s/s for each and both are in motion
A ball is thrown upwards and caught when it comes back down. In the absence of air resistance, the speed of the ball the instant before it is caught, would be...
the same as the speed it had when thrown upwards
After a rock that is thrown straight up reaches the top of its path and is starting to fall back down, its acceleration is (neglect air resistance)
the same as when it was at the top of its path
A ball is thrown upwards and caught when it comes back down. Neglecting air resistance, its speed when caught is
the same speed it had when thrown upwards
A bullet fired horizontally hits the ground in 0.5 seconds. If it had been fired with a much higher speed in the same direction, it would have hit the ground (neglecting the Earth's curvature and air resistance) in
the same time - 0.5 s
The acceleration due to gravity on earth is approximately
-10 m/s
A body falls freely from rest near the surface of the earth. The distance the object falls in 2 seconds is
-20 m
A ball is thrown straight upward at 20 m/s. Ideally (no air resistance) the ball will return to the thrower's hand with a velocity of
-20 m/s
A cannonball is launched from the ground at an angle of 30 degrees and a speed of 20 m/s. Ideally (no air resistance) the ball will land on the ground with a speed of
-20 m/s
If a car is traveling at a constant average speed of 60 kilometers per hour, how long does it take to travel 12 kilometers?
0.2 h
The vertical height attained by a basketball player who achieves a hang time of a full one second is about
1.2 m
Using the Pythagorean theorem, the resultant of a 6-N force in the Y-direction and a 8-N force in the X-direction is
10 N
A cannonball is fired at some angle into the air. In the first second it moves 10 meters horizontally. Assuming it doesn't hit the ground and there is no air resistance, how far does it move horizontally in the next second?
10 m
Suppose a small plane can fly at 200 km/h relative to the surrounding air. Suppose also that there is a 40-km/h tail wind. How fast does the plane's shadow move across the ground?
240 km/h
Mr. Vining is looking at new Garden apartment in downtown Scottsdale and is out on the balcony and decides to find out how far up he is. He takes out a water balloon (he now always carries a few thanks to Mr. Hill) and drops it over the railing. If it takes
-45 m
An object is released from a height of 11 m. Which one of the following best represents the displacement of the object 1.0 s after it falls freely from rest? (g = -10 m/s2)
-5.0 m
An object is dropped and falls freely to the ground with an acceleration of -9.8 m/s/s. If it is thrown upward at an angle instead, its acceleration after it is thrown would be
-9.8 m/s/s
An object travels 8 meters in the first second of travel, 8 meters again during the second second of travel, and 8 meters again during the third second. Its acceleration in meters per second per second is
0
What is the acceleration of a car that maintains a constant velocity of 100 km/h for 10 seconds?
0
A ball is thrown straight up. At the top of its path its instantaneous speed is
0 m/s
A freely falling object starts from rest. After falling for 1 second, it will have a speed of about
10 m/s
An apple falls from a tree and hits the ground 5 m below. It hits the ground with a speed of about
10 m/s
A ball is thrown 125 meters straight upward and then falls the same distance back to earth. Neglecting air resistance, its total time in the air is about
10 s
A car accelerates at 2 m/s/s. Assuming the car starts from rest, how much time does it need to accelerate to a speed of 20 m/s?
10 s
A rifle with a muzzle velocity of 100 m/s is fired horizontally from a tower. Neglecting air resistance, where will the bullet be 1 second later?
100 m downrange
What is the maximum resultant possible when adding a 3-N force to an 8-N force?
11 N
The average velocity of an object is 2 meters per second for 6.0 seconds. What is the total distance traveled by the object?
12 m
A runner travels 60.0 m at a steady speed of 5.0 m/s. The time taken is
12s
A car accelerates at 2 m/s2. Assuming the car starts from rest, how much time does it need to accelerate to a speed of 30 m/s?
15 s
A car accelerates uniformly from 3.0 m/s to 12.0 m/s in 4.5 s. The magnitude of the acceleration is
2 m/s/s
Mr. Vining sees Mr. Hill under his balcony. Mr. Vining drops a water balloon that falls freely for 2 seconds before striking Mr. Hill
20 m
If a freely falling object were somehow equipped with a speedometer on a planet where the acceleration due to gravity is 20 m/s/s then its speed reading would increase each second by
20 m/s
A radar transmitter sends out a pulse that is reflected from the moon's surface. The signal returns 2.7 s after it is sent ( i.e. it goes there and back ). What is the best estimate of the moon's distance from the earth if light travels at 3.0x108 m/s?
4.0x10 to the 8th m
In the absence of air resistance, the angle at which a thrown ball will go the farthest is
45 degrees
Suppose a car is moving in a straight line and steadily increases its speed. It moves from 35 km/h to 40 km/h the first second and from 40 km/h to 45 km/h the next second. What is the car's acceleration?
5 km/hr
Suppose a jumper claims a hang time of 2 seconds. Then that jumper must be able to jump a vertical distance of
5 m
Starting from rest, an object rolls freely down an incline that is 10 meters long in 2 seconds. The acceleration of the object is approximately
5 m/s
Which of the following is NOT a vector quantity? a. 5 N down b. 5 m/s c. 5 m/s East d. -10 m/s/s
5 m/s
Starting from rest, the distance a freely falling object will fall in 10 seconds is about
500 m
If a car increases its velocity from zero to 60 km/h in 10 seconds, it acceleration is
6 km/h/s
T or F: Average speed is defined as the time it takes for a trip divided by the distance.
False
TRUE OR FALSE: A unit of acceleration is meters per second
False
Possible units of time...
Miles per hour; light years per century; and kilometers per hour
Mr. Hill is very upset with Mr. Vining and he picks Mr. Vining up and throws him into the air. What can be said about Mr. Vining's acceleration after Mr. Hill releases him and before he hits the ground?
Mr. Vining's acceleration is always about -10 m/s/s
if you drop a feather and a coin at the same time in a vacuum tube, which will reach the bottom of the tube first?
Neither-they will both reach the bottom at the same time
T or F. Even though a car is slowing down, it is still accelerating, in the most general definition of acceleration.
True
Which of the following would NOT be considered a projectile? a. a cannonball thrown through the air b. a cannonball rolling down a slope c. a cannonball thrown straight up d. a cannonball rolling off the edge of a table
a cannonball rolling down a slope
Suppose an object is in free fall. Each second the object falls
a larger distance than in the second before
Speed is...
a measure of how fast something is moving; it is always measured in terms of a unitof distance divided by a unit of time; and the distance covered per unit time.
A ball is thrown straight up. At the top of its path its acceleration is
about 10 m/s
When something falls to the ground, it accelerates. This acceleration is called the acceleration due to gravity and is symbolized by the letter g. What is the value of g on Earth's surface?
about 10 m/s
It takes 6 s for a stone to fall to the bottom of a mineshaft. How deep is the shaft?
about 180 m
if a freely falling object were somehow equipped with a speedometer, its speed reading would increase each second by
about 20 m/s
In the absence of air resistance, objects fall at a constant
acceleration
A ball thrown in the air will never go as far as physics ideally would predict because
air friction slows the ball
In the absence of air friction, the vertical component of a projectile's velocity doesn't change as the projectile moves.
always false
In the absence of air friction, the horizontal component of a projectile's velocity doesn't change as the projectile moves.
always true
At what part of a path does a projectile have minimum speed?
at the top of its path
If an object falls with constant acceleration, the velocity of the object must
continually change by the same amount each second
A ball tossed vertically upward rises, reaches its highest point, and then falls back to its starting point. During this time the acceleration of the ball is always
directed downward
The area under a velocity-time graph represents
displacement
The two measurements necessary for calculating average speed are
distance and time
A ball is thrown into the air at some angle. At the very top of the ball's path, its velocity is
entirely horizontal
A quantity that has both magnitude and direction is called a scalar.
false
A quantity that has only magnitude is called a vector
false
T or F: If a body has an acceleration of -3 m/s/s, it MUST be slowing down.
false
T or F: While driving a car, it is possible to make a turn without accelerating if you keep the speed constant while turning.
false
True or False: A ball is thrown into the air. At the highest point, the ball has zero velocity and zero acceleration.
false
Consider drops of water leaking from a water faucet. As the drops fall they
get farther apart
When you look at the speedometer in a moving car, you can see the cars...
instantaneous speed
When a basketball player jumps to make a shot, once the feet are off the floor, the jumper's acceleration
is g no more, no less
Which of the following is NOT an acceleration unit?
km/s
The hang time (time one's feet are off the ground in a jump) for most athletes is
less than one second
A ball is thrown upwards and caught when it comes back down. In the presence of air resistance, the speed with which it is caught is
less than the speed it had when thrown upwards
A scalar is a quantity that has
magnitude
A vector is a quantity that has
magnitude and direction
At the instant a ball is thrown horizontally with a large force, an identical ball is dropped from the same height. Which ball hits the ground first?
neither-they both hit the ground at the same time
If a projectile is fired straight up at a speed of 10 m/s, the time it takes to reach the top of its path is about
seconds
Galileo's use of inclined planes allowed him to effectively
slow down the acceleration of free fall
Change in velocity can be obtained from
the area under an acceleration-time graph
If you drop a feather and a coin at the same tie in a tube filled with air, which will reach the bottom first?
the coin
Which one of the following statements correctly describes the motion of an object depicted by the position vs. time graph below? a) The object has non-uniform motion b) The object has constant non-zero acceleration c) The object has constant velocity d) The object has an increasing acceleration e) The object has increasing velocity
the object has a constant velocity
Drop a rock from a 5 m height and it accelerates at -10 m/s/s and strikes the ground 1 s later. Drop the same rock from a height of 2.5 m and its acceleration of the fall is
the same
two balls that are exactly the same size and shape. One ball is made out of aluminum and has a mass of a 0.5 kg. The other one is made out of uranium (its covered with lead so that no radiation leaks out) and has a mass of a 6.0 kg. If they are released at the same instant from the same height of 20 m they will reach the ground at
the same time with the same speeds
T or F: An object thrown straight up has a positive velocity and a negative acceleration.
true
T or F: If a body travels at constant speed, then the distance it travels varies directly with the time elapsed.
true
On a position vs. time graph, the slope of the line represents the
velocity
Acceleration is defined as the CHANGE in...
velocity divided by time interval
As an object falls freely in a vacuum, its...
velocity increases
As an object freely falls, its
velocity increases
Suppose you are in a car that is going around a curve. The speedometer reads a constant 30 miles per hour. What is not true?
velocity is constant
When a rock thrown straight upwards gets to the exact top of its path, its
velocity is zero, and its acceleration is about -10 m/s/s