Physics quizes
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 always
less than the speed when it was thrown upward
In science, facts
may change
Scientists repeat experimental findings in order to
neither a or b
If two objects are falling at terminal velocity, this means that
one may be going faster than the other, but both fall at a uniform speed
Of the sciences known as physics, chemistry, and biology, the most basic is
physics
An object falls freely from rest on a planet where the acceleration due to gravity is 20 meters per second squared. After 5 seconds, the object will have a speed of
100m/s (20)5
Disregarding air drag, how fast must you toss a ball straight up in order for it to take 2 seconds to return to the level from which you tossed it?
10m/s
A man leans over the edge of a cliff and throws a rock upward at 5 m/s. Neglecting air resistance, two seconds later the rock's speed is about
15 m/second
It takes 6 seconds for a stone to fall to the bottom of a mine shaft. How deep is the shaft?
180m 5(6)^2
A pot falls from a ledge and hits the ground 45 m below. The speed with which it hits the ground is
30m/second 5(3)^2
Ten seconds after starting from rest, a car is moving at 40 m/s. What is the car's acceleration in meters per second?
4m/s
If a car accelerates from rest at 2 meters per second per second, its speed 3 seconds later will be about
6 meters per second
At one instant an object in free fall is moving downward at 50 meters per second. One second later its speed should be about
60m/s
When a scientist is dishonest and reports false information, he or she
do not receive any form of excuse or second chance
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
greater than the second before
Science is a body of knowledge that goes back to
humankinds beginings
Most natural phenomena we wonder about
involve several scientific disciplines
Galileo's use of inclined planes allowed him to effectively
slow down the acceleration of free fall.
The amount of air resistance acting on a parachute is determined primarily by
speed and cross-sectional area
Terminal velocity for a parachutist means
the force of air resistance equals the force of gravity
Drop a rock from a 5m 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 fall is about
the same amount
What is the difference between an action force and a reaction force?
there is no difference
While an object near the earth's surface is in free fall , its
velocity increases
The scientific method is a method for
Gaining new knowledge
Using science to analyze nature
adds depth to our understanding and therefore adds to our appreciation of nature.
The muzzle velocity of a bullet fired from a new rifle is 100 m/s. Neglecting air resistance, at the end of one second a bullet fired straight up into the air will have traveled a distance of about
(100-5)m
Which of the following involves passion, talent, and intelligence?
art, literature, music, science
A heavy object and a light object are dropped at the same time from rest in a vacuum. The heavier object reaches the ground
at the same time as the lighter object
The two measurements necessary for calculating average speed are
distance and 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
1 second
What effect does increasing the parachute's size have on the air resistance?
Air resistance increases
Since action and reaction are exactly equal and oppositely directed, how can there ever be a net force on an object?
The action force doesn't act on the same object as the reaction force
Since movement of an object or system requires a net force be applied to it, how can this occur if all action forces have opposite and equal reaction forces?
The action force doesn't act on the same object as the reaction force
Someone standing at the edge of a cliff throws one ball straight up and another ball straight down at the same initial speed. Neglecting air resistance, the ball to hit the ground below the cliff with the greater speed will be
They will both have the same speed.
Which of the following are true about the significance of air resistance in affecting the parachute's motion?
When W and m are large, R is insignificant unless the object has a big cross-sectional area.
