physics Module 1
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
(100 - 5) m
Which of the following is not a vector quantity?
- speed vector quantity: velocity, acceleration
A mosquito flying at 3 m/s that encounters a breeze blowing at 3 m/s in the opposite direction has a speed of
0 m/s
An object covers a distance of 8 meters in the first second of travel, another 8 meters during the next second, and 8 meters again during the third second. Its acceleration is
0 m/s2.
A block pulled to the left with 15 N and to the right with 5 N at the same time experiences a net force of
10 N
The support force on a 10-N book at rest on a table is
10 N.
When you walk at an average speed of 4 m/s, in 5 s you'll cover a distance of
10 m
An apple falls from a tree and hits the ground 5 meters below with a speed of about
10 m/s
If you throw a ball straight downward (in the absence of air resistance), after leaving your hand its acceleration is
10 m/s^2
A ball is projected 125 meters straight upward and then falls the same distance back to its starting point. Neglecting air resistance, its total time in the air is about
10 s.
An 80-km/h airplane caught in a 60-km/h crosswind has a resultant speed of
100 km/h.
A pair of 10-N vectors at right angles to each other has a resultant of about
14 N
An airplane that flies at 100 km/h in a 100-km/h crosswind has a ground speed of
141 km/h
A tree stump is pulled northward by a 10-N force at the same time a 25 -N force pulls it southward. The resultant force has a magnitude of
15 N
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
15 m/s
Phil 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
15 m/s.
The time it takes a car to attain a speed of 30 m/s when accelerating from rest at 2 m/s2 is
15 s.
The minimum number of forces that act on a book resting on a table is
2
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?
20 m/s
An object falls freely from rest on a planet where the acceleration due to gravity is twice as much as on Earth. In the first 5 seconds it falls a distance of
250 m.
A pot that falls from a ledge and hits the ground 45 m below hits the ground at
30 m/s
Burl and Paul have a total weight of 1300 N. The tensions in the supporting ropes that support their scaffold add to 1700 N. The weight of the scaffold itself must be
400 N
A humming bird flying at 4 km/h that gets caught in a 3 -km/h crosswind has a resultant speed of about
5 km/h
One half second after starting from rest, a freely falling object will have a speed of about
5 m/s
Neglecting air resistance, a ball projected straight upward so it remains in the air for 10 seconds needs an initial speed of
50 m/s.
Jason weighs 150 N and sits on his big brother's shoulders. Big brother weighs 400 N. The support force supplied by the floor must be
550 N.
A humming bird flying at 4km/h that gets caught in a 3-km/h crosswind has a resultant speed of about
5km/h
A mosquito flying at 3 m/s that encounters a breeze blowing at 3 m/s in the same direction has a speed of
6 m/s
A car's speed 3 seconds after accelerating from rest at 2 m/s2 is
6 m/s.
If a car increases its velocity from zero to 60 m/s in 10 seconds, its acceleration is
6 m/s^2.
At one instant an object in free fall is moving downward at 50 m/s. One second later its speed is
60 m/s
A vehicle undergoes acceleration when it
All of the above A) gains speed. B) loses speed. C) changes its direction.
Science is a body of knowledge that
All of the above (describes order in nature, is an ongoing human activity and condenses knowledge into testable laws)
When a pair of 10-N forces act on a box of candy, the net force on the box is
Any of the above depending on the directions of forces (zero, about 14N, 20N)
A theory in the field of science is
a synthesis of a large body of well-tested knowledge
A package falls off a truck that is moving at 30 m/s. Neglecting air resistance, the horizontal speed of the package just before it hits the ground is
about 30 m/s
If Nellie hangs from a horizontal bar that is supported by four vertical ropes, the tension in the ropes
add to equal her weight
Which of the following is a scientific statement?
candy Bon Bons contain no sugar
Katelyn runs along the aisle of a train that moves at 8 m/s. Her speed relative to the floor is 3 m/s. Her speed relative to an observer at rest on the ground is
either depending on her running direction (5m/s, 11m/s)
A sheet of paper can be quickly jerked beneath aa container of milk without toppling, which best demonstrates
inertia
If your automobile runs out of fuel while you are driving, the engine stops. You don't come to an abrupt stop due to
inertia
Which concept is being illustrated when a tablecloth is quickly yanked beneath dishes resting on a table?
inertia
The speedometer of an automobile reads
instantaneous speed
A force is a vector quantity because it has both
magnitude and direction
Phil Physiker standing at the edge of a cliff throws one ball straight up and another ball straight down, both with the same speed. Neglecting air resistance, which ball hits the ground below with the greater speed?
neither, both hit with the same speed
The force that causes Earth to orbit the Sun is due to gravity, while the force needed to keep Earth moving as it circles the Sun is
no force at all
When a rocket ship gaining speed in outer space runs out of fuel, it
no longer gains speed.
Inertia is defined as a
property of matter
The accelerations possible for a ball on an inclined plane
range from g to infinity.
The statement, "There are regions beneath Earth's crust that will always be beyond the reach of scientific investigation" is
speculation
Burl and Paul paint signs together on a scaffold. Compared to their weights plus the weight of the scaffold, the sum of tensions in the supporting ropes is
the same.
The synthesis of a large collection of information that contains well-tested and verified hypotheses about certain aspects of the world is known as a scientific
theory
The equilibrium rule applies to
vector quantities
Earth continually moves about 30 km/s through space, which means the wall you stand next to also is moving at 30 km/s. When you jump vertically the wall doesn't slam into you because
you're moving horizontally just as fast as the wall
While you are standing in the aisle of a bus, the driver suddenly makes a left turn. You lurch to the right due to
your tendency to keep moving forward
The net force on any object in equilibrium is
zero
A cart changes its speed from 90 m/s to 100 m/s in 10 seconds. During this interval its acceleration is
1 m/s2
An object at rest near the surface of a distant planet starts to fall freely. If the acceleration there is twice that of the Earth, its speed one second later would be
20 m/s
A ball starting from rest at the top of an inclined plane accelerates at 2 m/s2 and reaches the bottom of the plane in 3 seconds. What is the length of the plane?
9 m
A truly educated person is knowledgeable about
all of the above (science, religion, and the arts)
Eratosthenes' measurements of Earth's size involved
all of the above - a deep well in Syene. - a pillar's shadow in Alexandria. - surveying the distance between Alexandria and Syene
When the Sun shines on the Moon, the Moon casts a shadow
all of the above (all the times, that sometimes falls on Earth, that is tapered)
To a fair approximation, Early Greek knew the
all of the above (size of the Moon, size of Earth, Earth-Moon distance)
Facts in the field of science
are changeable
If you toss a coin straight upward while in a train moving at constant velocity, the coin will land
as if you were at rest
When you quickly jerk a cart forward that has a ball resting in the middle, the
back of the cart hits the ball.
If an object moves with constant acceleration, its velocity must
change by the same amount each second
A simple method of measuring the distance between the Earth and the Moon is to place in your line of sight to the Moon a
coin
If no external forces act on a moving object, it will
continue moving at the same speed.
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
A moving van with a stone lightly glued to the midpoint of its ceiling smoothly moves at constant velocity. When the glue gives way, the stone falls and hits the floor
exactly below the midpoint of the ceiling
Pseudoscience is best characterized as being
fake
Whirl a rock at the end of a string and it follows a circular path. If the string breaks, the tendency of the rock is to
follow a straight-line path.
When we see a half Moon in the sky, the lines between Earth, Moon, and Sun
form a right triangle.
Suspend your body from a pair of ropes slightly angled from the vertical and the tension in each rope will be
greater than half your weight
When Nellie Newton hangs by the ends of a rope draped over a large pulley, the tension in each supporting vertical strand is
half her weight.
Suspend your body from a pair of vertical ropes and the tension in each rope will be
half your weight
Suspend your body from a pair of vertical ropes and the tension in each rope will be
half your weight.
An educated scientific guess is a
hypothesis
The synthesis of a large collection of information that contains well-tested and verified hypotheses about certain aspects of the world is known as a scientific
hypothesis
Spots of sunlight on the ground cast through openings between leaves in trees above are actually
images of the Sun
If you toss a coin straight upward in train that gains speed while the coin is in the air, the coin will land
in back of you.
The distance a freely falling object falls from rest in one -half second is
none of the above 2m,6m,4m
While a car travels around a circular track at a constant speed, its
none of the above A) acceleration is zero. B) velocity is zero. C) inertia is zero.
Which of the following is a vector quantity?
none of the above NONE OF THESE -mass -area -volume
A hockey puck is set in motion across a frozen pond. If ice friction and air resistance are neglected, the force required to keep the puck sliding at constant velocity is
none of the above (A) equal to its weight. B) equal to its weight divided by its mass. C) equal to its mass times its weight)
The distance a freely falling object falls from rest in one-half second is
none of thee above (4m,6m,2m)
A hockey puck sliding across the ice finally comes to rest because
of friction
While an iron block near the Earth's surface is in free fall, it undergoes an increase in
speed
When no forces act on moving objects their paths are normally
straight lines
When Nellie Newton hangs at rest in the middle of a clothesline, tensions will NOT be the same in each side of the rope when
the angles at each side of the rope are unequal
When Nellie Newton hangs at rest in the middle of a clothesline, tensions will be the same in each side of the rope when
the angles for both sides of the rope are equal
When Nellie Newton hangs at rest in the middle of a clothesline, tensions will be the same in each side of the rope when
the angles for both sides of the rope are equal.
A ball is thrown upwards and returns to the same location. Compared with its initial speed its speed when it returns is about
the same
The net force acting on an insect falling downward at constant velocity is
zero
Nellie pulls with a force of 50 N on a horizontal rope tied to a tree at rest. The net force on the rope is
zero and rope tension is 50 N